In a crop of viral videos featuring Tom Cruise, it's not the actor's magic trick nor his joke-telling that's deceptive — but the fact that it's not actually Tom Cruise at all. The videos, uploaded to TikTok in recent weeks by the account @deeptomcruise, have raised new fears over the proliferation of believable deepfakes — the nickname for media generated by artificial intelligence technology showing phony events that often seem realistic enough to dupe an audience.