When young inventor Bob Moore fails in his efforts to provide his father, a safe manufacturer, with a lock that is burglar proof, he contacts The "Eel," the most talented safecracker in the city, to offer him a job in his factory. The Eel, deciding to go straight, accepts the offer, but when he later learns that Irene Hardin has been given a valuable necklace by her father, The Eel plans one last job to secure Irene's pearls. Meanwhile, Irene's father, also a safe manufacturer, places the pearls in his own safe and tells Bob that if he can open it, Irene will be his. Bob, in love with Irene, opens the safe and places the pearls on the handle. After he departs, The Eel enters the house and steals the pearls. Bob is accused of the crime, and to exonerate himself, pursues The Eel. After a lively fight, Bob recovers the necklace and returns home to claim his bride.