Penny Singleton (born Mariana Dorothy McNulty, September 15, 1908[1] – November 12, 2003) was an American actress and labor leader.

She testified before a Senate subcommittee in 1962 on the union's treatment of women variety workers, and led a strike of the Radio City Rockettes in 1967.

[4] Singleton sang at a silent movie theater, and toured in vaudeville as part of an act called "The Kiddie Kabaret".

She sang and danced with Milton Berle, whom she had known since childhood, and actor Gene Raymond, and appeared on Broadway in Jack Benny's The Great Temptations.

She was cast opposite Arthur Lake (as Dagwood) in the feature film Blondie in 1938, based on the comic strip by Chic Young.

As Dagwood and Blondie Bumstead, they proved so popular that a succession of 27 sequels was made from 1938 until 1950, with the radio show ending the same year.

[11][14] She testified on the exploitation of women in variety work, and the union's shortcomings in representing those workers, before a United States Senate subcommittee in 1962.

[15] "I charge here and now that the exotic and strip artists have been abandoned and made outcasts by the very union to which they pay dues for representation and protection," she announced to the subcommittee.

With over 100 cast members, she led a slowdown in the performance in Hershey, Pennsylvania, followed by a walkout in Ft. Wayne, Indiana, and a settlement the next week in Houston, Texas.