"Star Trek: Deep Space Nine" signs off Wednesday at 10 on WDCA with a two-hour finale tying up all the plot threads of the past seven seasons and including special effects and many guest stars.

The series has four Emmys, two Hugo Awards for writing and the 1996 Screen Actors Guild Award for "outstanding portrayal of the American scene."

Avery Brooks plays Capt. Benjamin Sisko. The cast also includes Rene Auberjonois, Colm Meaney, Cirroc Lofton, Alexander Siddig, Nana Visitor, Michael Dorn, Nicole deBoer and Armin Shimerman.

ALSO THIS WEEK

P.O.V. Tuesday at 10 on WETA, Thursday at 10:30 on MPT

Michael J. Moore's "The Legacy: Murder & Media, Politics and Prisons" begins the series' summer season of independent films. Moore tells the story behind California's 1994 "three strikes and you're out" initiative by following two grief-stricken fathers -- once fervent allies, but now bitter rivals.

STEALING TIME: THE NEW SCIENCE OF AGING

Wednesday at 8 on PBS

We live during a time of discovery so revolutionary that we may be able eventually to double or even triple our record 76.5-year life span, believes executive producer John Rubin. Through reports and interviews, this three-hour program contends that the forces that control aging will soon be in our hands.

The first hour explores the natural history of aging; the second explains the aging process and asks what can be done about it; the third looks at the aging brain and disputes the idea that brain cells begin dying after a certain age.

CAPTION: Two "Star Trek" stalwarts: Armin Shimerman, above, as the crafty Quark, and Michael Dorn as Lt. Cdr. Worf.