John de Lancie is an American actor, producer, musician, and writer. Television credits include Q on UPN’s Star Trek: The Next Generation/Deep Space Nine/Voyager, Colonel Frank Simmons on Syfy's Stargate SG-1, and Donald Margolis on AMC's Breaking Bad.

Film credits include The Kite Runner, Reign Over Me, Saving Private Ryan, The Lost World, Trekkies, Without Warning, Fearless, The Fisher King, The Miracle of Kathy Miller, and The Onion Field.

Theatre credits include Mr. Wolf in Mr. Wolf and Basilio in Life is a Dream (South Coast Repertory); Pierre Curie in Radiance: The Passion of Marie Curie (Geffen Playhouse); and General Felix Barriaux in Resurrection Blues (Old Globe Theatre).

Together with Leonard Nimoy, John created Alien Voices, a company producing radio-style dramatization of classic science fiction. Collaborated works include The Time Machine, A Journey to the Center of the Earth, The Lost World, The Invisible Man, and The First Men in the Moon.