David Harbour sparks Avengers: Doomsday speculation with potential spoiler

Actor David Harbour, who reprises his role as Alexei Shostakov (Red Guardian) in the upcoming Marvel film ‘Avengers: Doomsday’, has sparked intense fan speculation following a recent interview with Variety. When asked to recite a line of dialogue from the film out of context, Harbour delivered the phrase, “You… are Tony Stark,” in a deadpan Russian accent.

While it is unclear if the line is a genuine spoiler or a joke, the comment has fueled theories regarding Robert Downey Jr.’s character. Downey Jr. is set to return to the Marvel Cinematic Universe as the villain Doctor Doom. Fans are debating whether the line suggests a multiverse variant of Tony Stark will appear, or if Doctor Doom will unmask to reveal a face identical to Stark to manipulate the Avengers.

Marvel Studios has not confirmed or denied the validity of the dialogue. The film is scheduled for release on December 18, 2026.