Master New York safecracker, "Taxi" Ivors, came to the town of Horseshoe Flat to avenge a friend's murder. Immediately he ran afoul of Barry Christian, the outlaw genius who terrorized Horseshoe Flat just as he did the entire West. Taxi is marked for destruction—until he gains the friendship of Arizona Jim Silver.

The legendary Silvertip has been on Christian's trail for years. Always the renegade is just within Silvertip's grasp, only to escape at the last moment. But now Christian is threatened by the strange partnership of Silvertip and Taxi—the brilliant lawman and the cunning criminal he has reformed.