The Thirteenth Hour (aka:The 13th Hour) is a 1927 American silent mystery film produced and distributed by Metro Goldwyn Mayer and directed by Chester Franklin.

[2][3] The film stars Lionel Barrymore in a role where, as noted criminologist Professor Leroy, he dons a weird series of disguises to hide a dark secret.

[4][5][6] This was the first film where Barrymore was cast opposite talented dogs,[7] and the first where he was cast as a serial killer.

[10] Junior detective Gray (Charles Delaney) discovers that the eccentric criminologist Professor Leroy (Lionel Barrymore) is both a crook and a murderer.

[11] A German Shepherd chases the elusive LeRoy throughout a large house filled with secret rooms.