'Sleeper Cell' When: 10 p.m. today through Wednesday and Dec. 11-14 and 8 p.m. Dec. 18 on Showtime. Starring: Oded Fehr, Michael Ealy. 'The Triangle' When: 9 p.m. Monday, Tuesday, Wednesday on Sci Fi Channel. Starring: Eric Stoltz, Catherine Bell.

It's about time -- and the timing couldn't be better. After years of struggling in the shadow of HBO, Showtime finally has a gritty drama worth crowing about.

"Sleeper Cell," a 10-part series about an FBI agent who infiltrates a Los Angeles terrorist group, premieres tonight at 10 just as HBO is about to hibernate for the winter (there will be no new episodes of the Sunday night series until March). Smart, thrilling and politically timely, "Sleeper Cell" works overtime to mix believable character drama with jolts of surprising plot twists.

Though they share a tone of tension and themes of sacrifice, "24" plays more like an outlandish comic book compared to "Sleeper Cell," a layered drama about multi-dimensional character, some of whom are terrorists.

Some viewers will, no doubt, object to any characterization of terrorists as anything other than evil incarnate. "Sleeper Cell" is not for those viewers. The less black-and-white reality is that just as no one is all good, neither is anyone all evil. And we are all hypocrites on some level.

For the Muslim extremists of "Sleeper Cell," that hypocrisy comes in multiple forms. Cell leader Farik (Oded Fehr) poses as an observant Jew and says, "I justify anything that will further our cause." Former French skinhead Christian (Alex Nesic) cheats on his wife, which goes against his faith.

Even for the hero of "Sleeper Cell," African-American Muslim Darwyn al-Sayeed (Michael Ealy), there's a willingness to let the ends justify the means, as tonight's premiere episode demonstrates.

Ealy, an actor I wasn't familiar with before "Sleeper Cell," is a stand out and a well-suited match for charismatic Fehr, who plays the terror attack mastermind with a single-mindedness and devotion that would be admirable if not for his evil intentions.

Showtime is rolling out "Sleeper Cell" in an unusual pattern, allowing the entire season to unspool over the next three weeks, with new episodes at 10 p.m. Sunday through Wednesday this week and next and the edge-of-your-seat (but a little overly convenient and "24"-like) two-hour finale on Dec. 18.

Particularly noteworthy episodes include those airing Dec. 11 (the cell meets up with another would-be terrorist who "did time at Shuman Detention Center" in Pittsburgh) and Dec. 13 (excellent plot twist).

'The Triangle'

Somewhere within this bloated six-hour miniseries there's a lean, mean four-hour miniseries trying to escape.

Sci Fi Channel's latest epic, "The Triangle" (9 p.m. Monday through Wednesday), is certainly better than last year's ho-hum "Legend of Earthsea," but with an all-star roster of producers, including Bryan "X-Men" Singer and Dean "Independence Day" Devlin, you expect something better than what "The Triangle" turns out to be.

It starts off promisingly enough as billionaire shipping magnate Eric Benirall (Sam Neill, "Jurassic Park") offers four experts $5 million apiece if they can solve the mystery of the Bermuda Triangle and the reason so many of his ships and their crews keep disappearing there.

The fantastic four include a psychic (Bruce Davison), an ocean engineer (Catherine Bell, "JAG"), a meteorology professor (Michael Rodgers) and a tabloid journalist (Eric Stoltz). (If we were playing "which one of these things doesn't belong," I think Stoltz would lose his gig.)

Director Craig Baxley ("Stephen King's Storm of the Century") tries to make the most of a script by Rockne S. O'Bannon, who recycles the notion of wormholes used in his "Farscape" series. And in his first installment, "The Triangle" holds potential as it hints at the possibility of time travel being an element of the Bermuda Triangle mystery.

It starts to bog down in the second night as a government conspiracy enters the story, and then the mumbo jumbo gets really heavy in the final installment. If only the story had been tightened up to fit into two nights, "The Triangle" might have been a more satisfying cable spectacle.