Weiskopf first tried comedy writing at the suggestion of friends Norman Panama and Melvin Frank. Panama and Frank lured him to Hollywood in 1940, where he managed to sell some jokes to Bob Hope for his radio program. From there, he later wrote for radio, for Eddie Cantor'sThe Eddie Cantor Show, and Rudy Vallée for his Rudy Vallee's Sealtest Program,[2] he would in later years, write comedy material for Fred Allen, Danny Thomas, Red Skelton, Phyllis Diller and Carol Burnett.
After the attack on Pearl Harbor on December 7, 1941, he sent his new bride, the former Eileen Ito, east to avoid the internment camps, and moved in with fellow Rudy Vallee writer Jess Oppenheimer (who 13 years later would hire his former roommate to write for I Love Lucy). Weiskopf and his wife Eileen were reunited a few months later when he moved to New York City, where he was hired to write radio comedy for the comedian-actor Fred Allen. When Weiskopf received a draft notice ordering him to report on June 1, 1942, he requested a two-week delay so that he could finish writing the last two Fred Allen shows of the season. The Draft Board summarily rejected his request, explaining, "Everybody knows Fred Allen writes his own material."[3][4]
The creative partnership and friendship with Bob Schiller began in 1953, when Weiskopf — who was also a comedy writer — had just relocated to Los Angeles from New York City, and his wife began searching for a school for their youngest son Kim, to attend; Schiller's first wife had recommended a school for Kim to Weiskopf's wife, and also told her that Schiller was looking for a partner. The two collaborated for the first time in writing a single radio script for the Our Miss Brooks show, before delving into the new media of network television together, writing for such popular 1950s shows such as Make Room for Daddy, which starred Danny Thomas, The Bob Cummings Show, I Love Lucy, the TV adaptation of the popular radio series My Favorite Husband, The Lucy-Desi Comedy Hour, and The Ann Sothern Show, which they co-created.
Weiskopf died in Los Angeles on February 20, 2001; he was survived by his wife, sons Kim and Walt and their grandchildren. His son Kim Weiskopf, who followed his father into the world of television comedy writing, died of pancreatic cancer at the age of 62 at his home in Encino, California.[5][2]