LOS ANGELES (AP) -- After four years, the mission is over for "Star Trek: Enterprise."

The prequel to the original ''Star Trek'' science fiction series will air its final episode in the United States on May 13, UPN and Paramount Network Television announced Wednesday.

The series will get a send-off that "salutes its contributions to the network and satisfies its loyal viewers," said UPN Entertainment President Dawn Ostroff. She didn't disclose details.

"Star Trek: Enterprise" debuted in September 2001. Scott Bakula stars as Capt. Jonathan Archer, along with John Billingsley, Jolene Blalock, Dominic Keating, Anthony Montgomery, Linda Park and Connor Trinneer.

The franchise included "Star Trek", "Star Trek: The Next Generation", "Star Trek: Deep Space Nine", "Star Trek: Voyager" and "Star Trek: Enterprise."

"Star Trek" movies also have been released.

While bidding goodbye to "Star Trek: Enterprise," the studio hinted at more "Star Trek" to come.

"We all look forward to a new chapter of this enduring franchise in the future," said Paramount Network Television President David Stapf.