News Avengers: Doomsday The Avengers: Doomsday Trailer Is Here to Remind You How Many People Are In This Movie It’s gonna take a minute for these Avengers to assemble, no? By Molly Templeton | Published on July 20, 2026 Screenshot: Marvel Studios Comment 0 Share New Share Screenshot: Marvel Studios Remember the chairs? Remember when Marvel let a video run forever in which they just gradually showed more and more directors’ chairs with actors’ names on them in order to introduce the cast of Avengers: Doomsday? I have not forgotten (or forgiven). What’s more, Marvel seems to be continuing this marketing approach. The first trailer for the next Avengers film is essentially the chairs video, but in costume. Here is a character! Here is a character! Here is a character! The gang’s all here. Well, almost all here. Some of us would like to see Nightcrawler (Alan Cumming), thank you. Avengers: Doomsday is a movie about how despite time-traveling or dying, Robert Downey Jr. and Chris Evans will return to the franchise. Thor (Chris Hemsworth) is scared. He intones, very seriously, that they are going to need a miracle. Chris Evans, shaggy and way less blonde, appears. This might have been more meaningful had we not already been informed that Chris Evans, despite all logic and previous films, would return. (Somehow, Loki also returns?) The one thing I want to know about this movie is what all these characters are doing in the same place at the same time. That will not be explained (yet, anyway). It is only important that you know that everyone is here and they must come together to face the man in the iron mask Doctor Doom (Downey Jr.). And by everyone, I mean: Sue Storm (Vanessa Kirby) Reed Richards (Pedro Pascal) Ben Grimm (Ebon Moss-Bachrach) Johnny Storm (Joseph Quinn) Shang-Chi (Simu Liu) Captain America (Anthony Mackie) Joaquin Torres (Danny Ramirez) Bucky Barnes (Sebastian Stan) Ant-Man (Paul Rudd) Loki (Tom Hiddleston) Shuri (Letitia Wright) M’Baku (Winston Duke) Red Guardian (David Harbour) John Walker (Wyatt Russell) Ava Starr (Hannah John-Kamen) Yelena Belova (Florence Pugh) Bob/Sentry (Lewis Pullman) Namor (Tenoch Huerta Mejía) Beast (Kelsey Grammer) Gambit (Channing Tatum) Charles Xavier (Patrick Stewart) Magneto (Ian McKellen) Mystique (Rebecca Romijn) Cyclops (James Marsden) We are really putting the concept of an ensemble cast to the test. Avengers: Doomsday is directed by Anthony and Joe Russo from a screenplay by Stephen McFeely and Michael Waldron. It’s in theaters December 18.[end-mark] The post The <i>Avengers: Doomsday</i> Trailer Is Here to Remind You How Many People Are In This Movie appeared first on Reactor.

News Star Trek: Strange New Worlds Strange New Worlds Season 4 Episode Titles Include an Intriguing Next Generation Reference Whose Enterprise is it anyway? By Matthew Byrd | Published on July 17, 2026 Photo: Paramount+ Comment 0 Share New Share Photo: Paramount+ The episode titles for the fourth season of Star Trek: Strange New Worlds were just released, and wouldn’t you know that they include an incredibly tantalizing Next Generation Easter egg. For reference, here are the 10 upcoming episode titles in order of release: 1: “Valles Marineris”2: “The Griffin Incident”3: “Human Best Friend”4: “A Case of Chiaroscuro”5: “Level-Five Transporter Accident”6: “Off-Hour”7: “Like Chronitons Through the Hourglass”8: “Orders of Magnitude”9: “Once La’An a Time”10: “Tomorrow’s Enterprise” While there are a few notable names on that list (Could “Level-Five Transporter Accident” be the puppet episode? What’s up with “Once La’An a Time?”) the early standout is undoubtedly “Tomorrow’s Enterprise.” On the surface, it is at least a callback to the beloved Season 3 episode of The Next Generation (“Yesterday’s Enterprise“), which showed an alternate timeline and a different version of the Enterprise. Naturally, the similar episode titles have sparked speculation that the Strange New Worlds‘ Season 4 finale could pull off a similar feat of timeline jumping. However, just to throw a reasonable dash of cold water on some of the more optimistic speculation, it’s likely that the episode title is just a cute reference. For that matter, it’s also possible that the wording refers to some kind of event that brings us closer to the events of Star Trek: TOS. We know the series is gradually heading in that direction, and a giant leap forward would certainly make for an appropriate finale that sets up the show’s fifth and final season. Still, one shouldn’t lose hope for another wild timeline manipulation adventure that sees the Strange New Worlds crew just get weird with it ahead of the end of all things (relatively speaking). It is, after all, what they often do best.[end-mark] The post <i>Strange New Worlds</i> Season 4 Episode Titles Include an Intriguing <i>Next Generation</i> Reference appeared first on Reactor.

News God of War God of War Will Have a New Lead After Ryan Hurst’s On-Set Injury Who will step into Kratos’ powerful boots? By Molly Templeton | Published on July 17, 2026 Credit: Justin Lubin/Prime Video Comment 0 Share New Share Credit: Justin Lubin/Prime Video This is a huge change for Prime Video’s God of War adaptation: After star Ryan Hurst’s on-set injury last month, the video game adaptation will recast the lead role of Kratos. As Deadline reports, Hurst tore a bicep, a serious injury that required surgery and will involve months of recovery. Deadline writes that “while Hurst’s full recovery is a priority, the period required for it was longer than the production shooting schedule could accommodate, leading to the difficult decision to recast the role.” Hurst had reportedly gained 40 pounds of muscle for the physically demanding role; as the character description says, “Kratos is Spartan by birth, and a god by nature. Raised in a martial culture, he rose to command armies in service of his homeland until one day he made a fateful deal with Ares, the Greek God of War and lost his soul in exchange for being victorious in battle.” Deadline says that four episodes had been completed when Hurst was injured—and now those will all have to be reshot with a new lead. That lead will join Callum Vinson, who plays Kratos’ son, along with castmates Mandy Patinkin (Odin), Ed Skrein (Baldur), Max Parker (Heimdall), Sonya Walger (Freya), Ólafur Darri Ólafsson (Thor), Teresa Palmer (Sif), Alastair Duncan (Mimir), Jeff Gulka (Sindri), and Danny Woodburn (Brok). God of War is expected to resume production this fall.[end-mark] The post <i>God of War</i> Will Have a New Lead After Ryan Hurst’s On-Set Injury appeared first on Reactor.

Books Science The Fermi Paradox, Percolation, and Inbreeding What do cheetahs and genetic bottlenecks have to do with interstellar colonization? Glad you asked… By James Davis Nicoll | Published on July 17, 2026 Credit: NASA/JPL-Caltech Comment 0 Share New Share Credit: NASA/JPL-Caltech Well-timed synchronicity is a wonderful thing. There’s nothing quite like the intellectual zing one experiences when one scientific presentation casts an unexpected light on a seemingly unrelated theory or idea. I was the beneficiary of this phenomenon last week, when scarcely twenty-eight years1 after reading Geoffrey Landis’ “The Fermi Paradox: An Approach Based on Percolation Theory,” a Lindsay Nikole video essay on an entirely unrelated matter suggested an interesting embellishment. But first! A quick background on the Fermi Paradox and on Percolation Theory as applied to it, for those of you who can’t be bothered to click the relevant links above. The Fermi Paradox isn’t really a paradox so much as a question for which we currently lack a compelling, satisfactory answer. Back of the envelope calculations suggest that even modest propulsion technology should be sufficient for a single technological species to spread throughout the galaxy in a geological instant. However, when we look around, there is no evidence that this has ever happened2. Thus, Enrico Fermi’s “But where is everybody?” Landis’ proposed explanation centred on the fact that even for technologically sophisticated species, interstellar colonization is likely to be difficult and expensive. Not every civilization will bother to invest scarce resources in projects that by the nature of light-speed lag and distance can do them no direct good. Furthermore, light-speed lag and distance mean that child civilizations must be functionally independent of parent cultures. That could be a full stop to further expansions, as there’s no guarantee that colony worlds will want to invest in spawning their own colonies. If the likelihood that colonies will be colonizers is low, then the effort peters out very quickly. Even when there is a civilizational commitment to colonization, the vagaries of chance will produce a patchy network of settled systems. Large swathes of space would remain unsettled. Perhaps an example is in order. For convenience, consider the Stellar Database entry for Sol. Suppose for the sake of argument that the longest practical distance for colonization is 6 light-years. There are at present two stellar systems within 6 light-years of Sol: Alpha Centauri and Barnard’s Star. The only stellar system within 6 light-years of Alpha Centauri is Sol. The only stellar systems within 6 light-years of Barnard’s Star are Sol and Ross 154. The only star within 6 light-years of Ross 154 is Barnard’s Star. Thus, the poor Solarians can only reach four systems before their technology is no longer up to the task3. Fans of the venerable tabletop roleplaying game 2300 AD know that increasing the maximum practical distance slightly (to 7.7 light-years) produces an interesting stellar road map where stars that are comparatively close to Sol while being farther than the maximum practical distance can only be reached via a circuitous chain of intermediary systems, if they can be reached at all. Tau Ceti, for example, is only about 12 light-years away but a ship limited to 7.7 light-year legs ends up covering 60 light-years as it dog-legs from system to system. This is merely a plot-enabling inconvenience in 2300 AD, which features faster-than-light travel. In a world where there is no FTL, where every intermediate system needs to be settled and developed before a flotilla can be dispatched further down the line, the chain of colonies might peter out well before reaching Tau Ceti. OK, so what does that have to do with Lindsay Nikole, who as you know is a zoologist and author with a colorful vocabulary whose interests, while expansive, appear to be entirely terrestrial? (That we know of.) Among Nikole’s interests: cats, big and otherwise. Thus, videos discussing various feline species. Thus, a video about cheetahs. Thus, a video titled “How cheetahs became genetically f***ed.” How did cheetahs become genetically f***ed? Long version, watch Nikole’s video. Short version: bottlenecks. Cheetahs experienced diverse catastrophes (see what I did there?) that left remnant populations with much smaller genetic diversity. Repeated catastrophes led to new bottlenecks, each of which further reduced overall species genetic diversity. This lack of diversity makes cheetahs vulnerable. Any disease that kills one cheetah will likely kill them all. We can apply Landis’ argument to interstellar colonization here: Each colonization is a genetic bottleneck. The first colony is a subset of the whole population of the mother world. The second one is limited to a subset of the first colony. The third… well, you can connect the dots. Let’s do some math. We’ll assume the colonizers aren’t idiots trying to emulate the Ptolemaic Dynasty… IN SPACE!4. Say they manage to preserve 90% of the genetic diversity of the species available to them. What does this look like in practice? Colony% of original diversity remaining1902813734665596537488439391034 Extend the sequence far enough and you probably get populations that are functionally so closely related you could do skin grafts between random individuals. While that would be tremendously convenient for the skin graft industry, it would leave the colonists in the same situation as cheetahs—so uniform that any circumstance that imperils one individual would imperil every member of their species on that planet. Which is bad. Maybe there’s a fix. If there isn’t—if genetic bottlenecks are an intractable problem—then what Landis called “percolation probability” would be low. To quote Landis, “For P<Pc, colonization will always terminate after a finite number of colonies.” Which is consistent with what we see.[end-mark] I often consider events that play out over geological time frames, so twenty-eight years is nothing. ︎We also don’t see any evidence of radio-based interstellar communication, something that is quite doable even with our modest technology. ︎At least for the moment. Stars move. ︎I hear the eugenicists protesting that this would be an excellent chance to select the very best genes, ensuring a planet of superhumans ten or twenty links down the line. But if we actually look at our own history, we note that the products of aristocratic inbreeding have fallen very short of superhuman. Second, which traits are desirable depends on context. The same traits that allow one to flourish in Toronto will serve you very badly at the bottom of the Marianas Trench. ︎ The post The Fermi Paradox, Percolation, and Inbreeding appeared first on Reactor.

News What to Watch What to Watch and Read This Weekend: The Air Is Smoke, the Lettuce Is Bad, but the Vampire Is Lestat Plus: Major outlets are apparently still shocked that women read fantasy By Molly Templeton | Published on July 17, 2026 Image Credit: Image: Sophie Giraud/AMC Comment 0 Share New Share Image Credit: Image: Sophie Giraud/AMC Friends on the other side of the country, I am so sorry. I know exactly what it’s like to try to go outside and be stymied by unbearably smoky air. Wear your masks, run your air purifiers, and maybe, you know, stay indoors as much as you can? It’s vile out there. As if this year has not been difficult enough, this summer has taken a hard turn into bonus-level terrible, what with the exploding diarrhea virus and the unbreathable air, and the knowledge that some of these things could be stopped—or at least ameliorated—if, as a nation, our priorities were different. (That’s about as diplomatic as I can be on that front.) While you’re avoiding the outside this weekend, perhaps you want to hang out with some vampires, or go to space, or think about hungry stars? As always, hug your friends, call your reps, and—given that it’s summer—stay hydrated, okay? Seven Episodes Is Not Enough: The Vampire Lestat In this house it is The Vampire Lestat Finale Week which means I am tearing my way through The Queen of the Damned—which had better be this show’s fourth season, goddammit! I need renewal news!—and buying Calvino novels (those two Calvino references have to mean something, right?) and also considering spending much of my Saturday rewatching the first six episodes of this all-too-short season. It’s like watching two long Marvel movies! I can do it! And I guess what I’m saying here is that you could, in theory, make time to do the same. The finale arrives Sunday on AMC/AMC+ and given the tumultuous events of last week’s episode, I am ever so slightly frothing at the mouth to see where this wild series goes, and how they wind it all up, and did I mention I need renewal news like, yesterday? I have a feeling they’ll make any big announcements next weekend at San Diego Comic Con. But I am impatient. “This Star Just Ate a Planet” This one both is and isn’t the plot of a novel: “This Star Just Ate a Planet, and It’s Not Done Yet” is the headline of a fascinating New York Times article about … well, it does what it says on the tin. “For many planets, it is their cosmic fate to one day become engulfed within their own stars, then slowly melted down into their constituent elements,” writes Becky Ferreira. Isn’t this what happens (in part) in Slow Gods? I admit I was so invested in the characters of that book that I may have glossed over the planetary mechanics. Anyway! It’s always kind of neat—and maybe a little terrifying—when these things happen close enough (relatively speaking) that our little (in the grand scheme of things) human tools and minds can witness them.  Speaking of Stars, Planets, and Drama… … Strange New World returns to our happy little screens next Thursday! While the show’s last season was frustrating, I remain eternally enthusiastic about hanging out with this cast, and eternally hopeful that maybe, just maybe, Paul Wesley will still get a show starring his version of Captain James T. Kirk. Given all the changes at Paramount, that might not be likely—but one can still hope. My specific hope for this season is that it does not spend a lot more time shoving various interesting characters at Spock in the hope that some love interest sticks. And also that La’an gets a lot of screen time. And also Pelia. And also … you know, honestly, it doesn’t matter; I’m going to watch it regardless. Star Trek: Strange New Worlds is back on Paramount Plus on July 23rd.  Apparently Women Just Discovered Fantasy This week, the usually quite good Guardian newsletter tackled romantasy, which was totally fine and good except when they wrote of the genre: “It also gives women an access point to fantasy, a traditionally male-heavy genre, both in authorship and fandom.” With all due respect to romantasy—which I do think has brought new readers into SFF!—I don’t think I have to tell Reactor readers that women have been writing and reading fantasy for as long as there has been fantasy. A statement like this erases a ton of work from a laundry list of incredible writers. So here’s my weekend suggestion for you: read a fantasy novel by a woman published at least 30 years ago. And for bonus points, look past the biggest names! I grew up almost exclusively reading fantasy by women, obsessed with authors like Jo Clayton, Melanie Rawn, Barbara Hambly, Diane Duane, Patricia Kennealy, Jennifer Roberson, Pamela F. Service, and Patricia McKillip. (I will note that in the mall bookstore in the ’80s and ’90s, one mostly found fantasy novels by white women. The diversity was not great.) There are so many more names; if you need a list to pore over, you might investigate James Davis Nicoll’s “Fighting Erasure” posts.  Honestly, twenty years ago I thought we were maybe finally through with the “Ooh, women have discovered genre!” conversation. But apparently not.[end-mark] The post What to Watch and Read This Weekend: The Air Is Smoke, the Lettuce Is Bad, but the Vampire Is Lestat appeared first on Reactor.