Abstract: Apparatus for preventing theft of an automobile having a rotatable steering shaft for steering the vehicle and an ignition mounted at a fixed position, includes three equiangularly disposed holes extending transversely through the steering shaft; a steering shaft locking pin movable between a locking position in any hole and an unlocking position out of the holes; and ignition shaft engageable with the steering shaft locking pin for moving the latter into and out of the holes; a dead bolt locking pin engaged by the ignition; a spring which moves the dead bolt locking pin into blocking relation to the steering shaft locking pin to prevent removal thereof from a hole in the steering shaft when the ignition is removed from its fixed position; the upper end of the dead bolt locking pin extending through a first slot in a steering wheel locking plate positioned about the steering shaft and engaging a horn spring to actuate a horn; a plate locking pin engaged by the ignition shaft and movable into a second slot in