Thunderbolts actor David Harbour has revealed what he describes as a spoiler for the upcoming Marvel film Avengers: Doomsday, though the claim is being treated with scepticism as it seems too far-fetched to be genuine. The comments have generated buzz among fans eager for details about the highly anticipated ensemble film, even as commentators question whether Harbour was joking, misdirecting, or simply speculating rather than sharing confirmed plot information.

Specific details of what Harbour actually said were not available in the source text provided, so the exact nature of the "spoiler" cannot be confirmed here. Avengers: Doomsday is one of Marvel Studios' most closely guarded upcoming projects, and cast members are frequently pressed for hints, with statements from actors like Harbour often treated cautiously by fans given Marvel's history of misdirection and secrecy around plot details.