A leading Hollywood figure has warned “it’s likely over for us”, after watching a widely disseminated AI-generated clip featuring Tom Cruise and Brad Pitt fighting.

Rhett Reese, co-writer of Deadpool & Wolverine, Zombieland and Now You See Me: Now You Don’t was reacting to a 15-second video showing Cruise and Pitt trading punches on a rubble-strewn bridge, posted by Irish film-maker Ruairí Robinson, director of 2013 sci-fi horror The Last Days on Mars. Reposting the clip on social media, Reese wrote: “I hate to say it. It’s likely over for us.”

He added: “In next to no time, one person is going to be able to sit at a computer and create a movie indistinguishable from what Hollywood now releases. True, if that person is no good, it will suck. But if that person possesses Christopher Nolan’s talent and taste (and someone like that will rapidly come along), it will be tremendous.”

Robinson said that the clip resulted from a “2 line prompt in Seedance 2”, referring to the AI video generator Seedance 2.0, released on Thursday by TikTok co-owners ByteDance.

The Motion Picture Association, the Hollywood trade association, accused ByteDance of “unauthorised use of US copyrighted works on a massive scale”.

Calling on ByteDance to “cease its infringing activity”, MPA chair and CEO Charles Rivkin said: “By launching a service that operates without meaningful safeguards against infringement, ByteDance is disregarding well-established copyright law that protects the rights of creators and underpins millions of American jobs.”

ByteDance, also the owner of TikTok outside of the US, has been contacted for comment.