What to Watch Before Avengers: Doomsday: The Essential List, What's Worth It, and What You Can Skip

Avengers: Endgame (2019)

The movie Doomsday keeps pointing at. The trailer hid Tony Stark’s snap in Doom’s tapestry. The Hall H footage has Doom telling the heroes they’ve lived “stolen lives” that must be given back. The Time Heist left branched timelines all over the place, and Steve Rogers’ trip back to Peggy is the thread half the circulating theories hang on. And here’s the tell that removes all doubt: Marvel is re-releasing Endgame in theaters on September 25, as Endgame Encore, with new footage attached that the Russos say bridges directly into Doomsday. When the studio itself schedules your rewatch, it’s essential. If it’s been years, watch Infinity War first (it’s in Tier Two for exactly that reason).

Loki, Seasons 1 and 2

The rulebook. Everything Doomsday appears to run on, branching timelines, variants, the consequences of breaking time, the TVA, He Who Remains, comes from this show, and it ends with Loki personally holding the multiverse together, which is a status quo Doomsday has to deal with. Loki is in the trailer in TVA gear with an ID card in hand. Tom Hiddleston is in the confirmed cast. Of every Disney+ series Marvel has made, this is the one that is not optional.

The Fantastic Four: First Steps (2025)

Doom’s introduction and, by every signal, his home turf. The mid-credits scene is the single most important minute of setup in the MCU right now: a cloaked Doom kneeling in front of Franklin Richards, the reality-shaping child, holding his mask. The Hall H footage has Sue Storm narrating Doom’s fall like someone who knew him (“he used to be kind”), and the panel confirmed Doom and Reed share real history. The Fantastic Four are central to this movie, Franklin is central to the theories, and this film is where all of it starts.

Thunderbolts* (2025)

The asterisk was the point: this team ends the movie as the New Avengers, and essentially the whole roster, Yelena, Bucky, Red Guardian, Ghost, John Walker, Bob, is in Doomsday’s confirmed cast. The post-credits scene is direct setup, the team detecting the Fantastic Four’s ship crossing into their universe, which is the exact three-universes collision the synopsis describes. And Sentry is a wild card powerful enough to matter in any cosmic fight. This is the newest team on the board and the one casual viewers are most likely to have skipped.

Doctor Strange in the Multiverse of Madness (2022)

The movie that defined the threat. Incursions, two universes colliding and destroying each other, are explained here, on screen, by an alternate-universe Illuminati, and the post-credits scene tells Strange to his face that his multiverse-hopping caused one. Every serious read of Doomsday’s plot runs through the word this movie introduced. Bonus receipts: it’s Patrick Stewart’s most recent appearance as Professor X, and the Illuminati it puts on screen is the same comics concept Hickman’s run, the one Doomsday is drawing on, is built around.

X-Men (2000) and X2 (2003)

Not MCU. Still essential, and the lists that skip them are doing their readers dirty. Stewart’s Xavier, McKellen’s Magneto, Marsden’s Cyclops, and Romijn’s Mystique are all confirmed in Doomsday, and Alan Cumming’s Nightcrawler, confirmed too, debuts in X2, which remains the best film the original franchise made. These two movies are the entire emotional foundation for the returning X-Men cast. The Hall H crowd lost its mind when Marsden’s Cyclops appeared in the comic-accurate suit. That reaction was twenty-six years of these films paying off.

Deadpool & Wolverine (2024)

The bridge between universes, and the proof of concept for everything Doomsday is attempting. The TVA on the big screen, a dying universe, what happens to a reality when its anchor is gone, and the send-off for the Fox era that Doomsday is now resurrecting. It’s also where Channing Tatum’s Gambit debuts, and Tatum is in the confirmed Doomsday cast. Add Ryan Reynolds crashing the Hall H panel in a brand-new Deadpool suit, and this one has graduated from fun to functional.