David Harbour Doubles Down on Red Guardian’s Mysterious ‘Avengers: Doomsday’ Countdown

If there’s one thing Marvel actors have mastered, it’s walking a tightrope between teasing fans and keeping a studio’s secrets safe. David Harbour has been balancing on that rope for months, and the Red Guardian star has now given ‘Avengers: Doomsday‘ fans another reason to speculate.

Harbour has played Alexei Shostakov since ‘Black Widow’ and returned in ‘Thunderbolts*’, where his character joined the group now known as the New Avengers alongside Bucky Barnes, Yelena, John Walker, Ava Starr and Bob Reynolds. He is expected back for ‘Avengers: Doomsday’, which arrives in theaters on December 18, 2026.

That ensemble has already produced one of the most talked-about spoiler scares of the year. To understand why his newest comment is getting attention, it helps to rewind to August.

In August, Variety asked Harbour to recite a line from the movie completely out of context. Speaking in his Red Guardian accent and pointing at the interviewer, he reportedly delivered a deadpan line in which Red Guardian tells someone they are Tony Stark.

The reaction was immediate. Robert Downey Jr. is playing Doctor Doom, and the line fueled theories that the villain shares a face with Tony Stark. One outlet even suggested it hinted that Doom unmasks in the film with Red Guardian in the room.

Harbour has since changed his story. Speaking to ScreenRant in October, he said he never said that, suggested the media makes this stuff up, and recalled that the line he gave was a countdown from five to one. He added that his Thunderbolts* co-star Wyatt Russell had sent him an article claiming he had ruined the movie, and he apologized just in case.

David Harbour reveals a Red Guardian line from ‘AVENGERS: DOOMSDAY’ “Five, four, three, two, one.” (via: comicconbrussels | IG) https://t.co/2mts24LWfD

— MCU Film News (@MCUFilmNews) October 26, 2026

Now Harbour has revisited the countdown. At an appearance at Comic Con Brussels, he revealed the Red Guardian line from ‘Avengers: Doomsday’, once again counting down from five to one.

It’s the same bit he teased to ScreenRant, where he jokingly called it a big spoiler. He said he counts down from five at one point in the film and that something very important happens afterward.

Whether he’s playing it straight or having fun at fans’ expense is anyone’s guess. Variety’s original article is still online, and Marvel hasn’t confirmed either version.

Nobody outside the production knows what the countdown leads to. One outlet quipped that apparently something is going to blow up in an ‘Avengers’ movie, which is a reasonable guess for any scene built around a ticking clock.

The comment also fits Harbour’s pattern of dropping cryptic hints. He told Deadline that the film will have a significant impact on the connection between Alexei and Yelena Belova, though he gave no specifics on how.

He also told Entertainment Weekly at San Diego Comic-Con that there’s trouble ahead between the New Avengers and the original Avengers. That matches what Marvel’s trailers have indicated, with Sam Wilson’s Avengers and Bucky’s New Avengers putting aside their issues to unite against a multiversal threat.

Whatever the truth behind the line, these moments are part of a wider promotional wave as the film nears. The movie features one of the biggest casts Marvel has ever assembled, including Anthony Mackie’s Captain America, Chris Hemsworth’s Thor, Chris Evans’ Steve Rogers, the Fantastic Four and the Fox-era X-Men.

Marvel has also been releasing new teasers in a steady stream. It has partnered with brands and even Major League Baseball, and presales have reportedly broken records in several markets.

Against that backdrop, a short clip from a fan convention can go a long way. Every fragment of dialogue becomes a puzzle for the community to dissect.

He used to be different. Avengers: Doomsday arrives in theaters everywhere December 18. Get your tickets now: https://t.co/J5PUbxvAkc https://t.co/OUutSMZneq

— Marvel Studios (@MarvelStudios) August 15, 2026

For now, the only certain thing is that the line has become part of the film’s pre-release mythology. Fans will have to wait until December to see whether the countdown signals a bomb, a portal or something else entirely.

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