A police prowl, when city detective McCallister, who is incorruptible, Ahern, whom he protects, and Sheridan, whom he dislikes, are assigned to the long vigil to pull in Harry Wheeler- a bank robber. With Ahern as an alibi, Sheridan is able to murder Wheeler, and with his eye on the money- kills again, and almost again, until McAllister is able to avenge his friend and save his girl. Not inscrutable, but busy.