Desc: The Perfect Alibi: Directed by Leo D. Maloney. With Leo D. Maloney, Josephine Hill, John Blocker, Whitehorse. Mack McGregor, a ranger, is engaged to Marion, daughter of Captain Atwood, the company commander. Mack and Marion find evidence implicating her brother, Rodney, in a robbery. On her pleas, Mack refuses to pursue the criminal and is dismissed from the service. Ollie Summers and Lon Elwell, the real culprits, blackmail Rodney, who, in desperation, plans to rob his father's safe. He does not follow through, and the crime is committed by Ollie and Lon. Captain Atwood arrives with Ollie and Lon to arrest his son, but Bullet, Mack's dog, uncovers evidence proving him innocent and then helps capture the two desperadoes.