A theatrical luminaire for entertainment and architectural applications includes a lamp socket accessible from the exterior of the luminaire housing. A lamp includes a base, a bulb on one side of the base and a handle on the other side. The handle is grasped to insert the lamp into the socket. When the base is mounted in the socket, the bulb extends through the socket into the luminaire and the handle remains accessible at the exterior of the luminaire. The lamp is mounted with a one-handed push and turn motion, and contacts on wings of the base engage socket contacts as the lamp is turned to its final position. The socket is mounted on a support that is adjustable relative to the luminaire housing to preserve the correct lamp positioning when the lamp is replaced.