Looks like the Blackouts were a live Hollywood variety show in the 1940s. Some great background here from Los Angeles Theaters:
“Ken Murray’s Blackouts” played the Hollywood Playhouse, 1735 Vine St., at a time the theatre was known as the El Capitan. The one on Hollywood Blvd. had been renamed the Paramount in 1942. Various editions of “Blackouts” began in 1942 and ran for seven years and 3,844 performances.
From Desi Arnaz, the Nicholas Brothers and Peg Leg Bates to bird acts and DAISY the wonder movie dog. It’s all show biz.
As for Ken Murray himself, he had a wide-ranging career from Queen for a Day to the Man who Shot Liberty Valance.
Photo by Monarch.