Claim: Legion is played by Dan Stevens, also known for his role in Beauty and the Beast.

Daniel Jonathan Stevens -LRB- born 10 October 1982 -RRB- is an English actor . He is best known for his role as Matthew Crawley in the ITV acclaimed period drama series Downton Abbey . He also starred as David in the thriller film The Guest , Sir Lancelot in Night at the Museum : Secret of the Tomb , and as The Beast/Prince in Walt Disney 's live action adaptation of Beauty and the Beast . He currently stars as David Haller in the FX series Legion .