Abstract: An alarm lock for securely locking both edges of an emergency exit door. A rigid, hollow housing mounts upon an existing door between opposing door facings. A pair of rigid, elongated rods is longitudinally displaceable within the housing between a locked position and an unlocked position. The rods are driven by a coupler confined within the housing and coupled to a rotatable crank controlled by a paddle arm handle assembly. The crank is journaled for rotation about a rigid axle which projects through the housing interior. Movement of the handle rotates the crank, selectively extending and retracting the rods into and out of engagement with the door casings. A panel mounted on the paddle arm clearly displays instructions for emergency use. When the handle is activated, a rigid follower associated with one of the rods forcibly contacts an alarm switch to activate an audible transducer. The alarm may be manually disarmed and reset by manipulation of a key switch.