Abstract: A locking mechanism is adapted to be attached to the inside surface (31) of a safe door (30) or the like. A key lock (12) with a bolt (18) secures to the inside of the door. A lock pin body (14) has a ledge (22) to which are secured lock pins (24) and depending from the ledge (22) is an actuator section (20) have vertical guide slots (48 and 50). A slide plate (16) is designed for movement on the face of actuator section (20). The slide plate (16) is biased against bolt (18) and has two slots (80 and 82). To unlock the safe door the lock bolt (18) is retracted by key or combination so that the slide plate latch follows under spring tension. A shaft extending from the door exterior through actuator section (20) and one of the guide slots (50) is engaged by one of the slots (80) of the slide plate latch and when rotated moves the body (14) down to disengage the lock pins (24) from their locking elements in the safe casing.