A guide to notable programs by BRUCE FRETTS. (Times are Eastern daylight and are subject to change.)

SERIES

It's tough to make a living doing performance art these days, so perhaps it's no surprise that two practitioners have turned up in recurring sitcom roles as shrinks. Monologuist Spalding Gray (Swimming to Cambodia, Monster in a Box) has taken THE NANNY (CBS, Wednesdays, 8-8:30 p.m.) as a patient, and his trademark deadpan provides a nice comic counterpoint to Fran Drescher's manic braying. Too bad the same can't be said for Mo Gaffney, who's a big bore as Paul Reiser and Helen Hunt's marital therapist on MAD ABOUT YOU (NBC, Tuesdays, 8-8:30 p.m.). Gaffney, who costarred with Kathy Najimy in the Off Broadway production The Kathy & Mo Show: Parallel Lives, also appeared earlier this season on Roseanne, where she's now listed as a consultant. Since Mad and Roseanne air at the same time, isn't that a conflict of interest?

After working in the sizable shadow of partner Andre Braugher for the past four years, Kyle Secor has finally come into his own on HOMICIDE: LIFE ON THE STREET (NBC, Fridays, 10-11 p.m.). No longer the squad's endearingly naive rookie, Secor's Tim Bayliss has begun to show an intriguing darker side this season (and Secor makes his directorial debut with the Jan. 31 episode). Nowhere was this more evident than in a recent episode in which we learned that Bayliss' obsession with child murders springs from the fact that he was sexually abused by his uncle. As Bayliss and Pembleton grilled a dead girl's mother (the shattering LaTanya Richardson), a surprise role reversal took place: The supersensitive Bayliss tried to bully her into a confession, while the stroke-enfeebled Pembleton played the good cop. With the recent on-screen romance between Reed Diamond and Michelle Forbes, Secor seems to have been liberated from his role as Homicide's resident sex symbol. He's acting with newfound abandon, and the results are thrilling.

Even as its scripts become increasingly ridiculous, the X-FILES (Fox, Sundays, 9-10 p.m.) continues to distinguish itself with inspired guest-star casting. The latest addition to the stellar roster that includes Peter Boyle (an Emmy winner as psychic Clyde Bruckman) and Charles Nelson Reilly (as spaced-out writer Jose Chung): Ruben Blades, whose quietly humorous turn as Conrad Lozano, a cowboy-hat-wearing immigration official single-handedly redeemed an otherwise absurd episode. Helping Agents Mulder (David Duchovny) and Scully (Gillian Anderson) track a monster known as el Chupacabra (''the goatsucker'' -- don't ask), Blades' Lozano seemed a spiritual cousin to the long-suffering lawman he played in Robert Redford's underrated 1988 movie, The Milagro Beanfield War. Blades has such an easygoing screen presence, it makes you almost glad he lost his recent bid for the Panamanian presidency. Too bad he can't reprise his role as Lozano, who ended up dead at the episode's end. Then again, this is The X-Files...