TV Line has learned that Dean Cain and Helen Slater have joined the cast of CBS' upcoming "Supergirl" pilot in unspecified roles.

Both actors have a lengthy history with DC Comics' Superman franchise. Dean Cain previously starred as Superman in "Lois & Clark: The New Adventures of Superman" for four seasons on ABC. He later appeared on the CW's "Smallville" as Dr. Curtis Knox. Slater starred as lead character Kara Zor-El in 1984's "Supergirl" feature film. She too had a guest-starring role on "Smallville" as Clark Kent's Kryptonian mother, Lara. Slater will star alongside the new Kara Zor-El, played by Melissa Benoist.

Cain and Slater are the latest additions to a fast-growing cast. In addition to series lead Benoist, "Supergirl" will also feature Mehcad Brooks as Jimmy Olsen, Laura Benanti as Alura Zor-El, Calista Flockhart as Cat Grant, Chlyer Leigh as Supergirl's sister Alex and David Harewood as Hank Henshaw.

This isn't the first time that a superhero actor has returned for a later adaptation. The CW's "Flash" series -- which shares producers Greg Berlanti and Andrew Kreisberg with "Supergirl" -- cast John Wesley Shipp, who portrayed the scarlet speedster in the early '90s series, as the new Barry Allen's father. Other actors from the previous "Flash" series, including Mark Hamill and Amanda Pays.