An apparatus for entraining and unlatching an elevator car door and a shaft door includes an electromagnet having a movable armature attached to a first bellows mounted on a wall of the car. An entraining and unlatching cam is attached to a second bellows which is mounted on the car door. The cam has stiffened cam entry surfaces, cam surfaces and front surface. The bellows are connected by a hose as a closed pneumatic system operating with below atmospheric pressure. When the electromagnet is not actuated, an internal compression spring in the second bellows extends the cam into engagement with rollers mounted on a shaft door to splay the rollers thereby unlatching the shaft door and entraining it with the car door. At the same time, the first bellows retracts the armature to unlatch the car door. When the electromagnet is actuated, the armature latches the car door and the second bellows retracts the cam to permit the rollers to fold toward one another thereby latching the shaft door. The movements of the bellows are detected by microswitches which are connected with a monitoring circuit which controls a pump to maintain the desired pressure in the system.