The cast if filling up quickly for Joss Whedon's latest adventure, the Fox science fiction series "Firefly." And once again, he has scored some big names in the business.

Gina Torres, who played Anna Espinosa in an October episode of "Alias," has joined the cast of "Firefly" as well as Ron Glass and Summer Glau, according to a report by The Hollywood Reporter.

Torres has made the television rounds, most notably playing Nebula in seven episodes of "Hercules: The Legendary Journeys" from 1997 to 1999. She also played Hel in "Cleopatra 2525" and Dr. Amy Ellis in the 1994 series "M.A.N.T.I.S."

Glass mostly recently appeared as Graham Redmond in "The Education of Max Bickford." He has voiced Randy Carmichael in the series "Rugrats" since 1992 and played Felix Unger in the failed 1982 series "The New Odd Couple." The 56-year-old is best known to genre fans for playing Loken in the "Star Trek: Voyager" episode "Nightingale," which aired in December 2000.

Glau will apparently play super genius River in the series. Not much is known about this actress, except that she played a dancer in an episode of "Angel."

The actors join a cast that already includes Nathan Fillion, Adam Baldwin and Jewel Staite. Fox Television already has given the series by "Buffy the Vampire Slayer" and "Angel" creator Whedon a 13-episode commitment.

According to reports, the series will take place several hundred years in the future and follows the crew of a transport ship. Whedon has described this pilot as a Western set in space, similar to what Gene Roddenberry did when he called "Star Trek" a "'Wagon Train' to the stars."