[citation needed] Lau studied playwriting at the University of Wisconsin, taking time off to serve in the United States Army Air Forces in World War II.

[2] Although his goal was to be a writer, he ended up acting simply because he found more jobs as an actor than as a playwright when he arrived in New York City seeking work.

He appeared frequently during the latter part of the show's run, especially during times when longtime series regular Ray Collins, who played Lt. Arthur Tragg, was absent.

Other shows in which Lau made appearances included Alfred Hitchcock Presents, Gunsmoke, Mike Hammer, Johnny Ringo, Have Gun – Will Travel, Peter Gunn, The Twilight Zone, The Time Tunnel, The Big Valley, Mission: Impossible, Cannon, Wagon Train, and The Six Million Dollar Man.

He would reunite with Raymond Burr, who played the title role in the Perry Mason series, in an episode of Ironside called "In the Forests of the Night".