Shows too smart for network television thrive on cable. Denis Leary’s irreverent cop comedy “The Job” went missing in action on ABC, so Leary changes uniforms and civil service exams to become a fireman on “Rescue Me” (9 p.m., FX).

Much like his “Job” character, Leary’s Tommy Gavin is a reluctant hero with serious emotional baggage. He’s on the verge of divorce and falling off the wagon. But in “Rescue” Leary’s character carries on meaningful conversations with friends, relatives and fellow firemen who happen to be dead.

At its best, “Rescue” captures the macho madness of a firehouse: the pranks and pecking order of a boy’s club, and the profanity, prejudices and gambling obsessions of men trying to save lives and protect their way of life as they risk death and battle red tape and creeping political correctness. In the pilot’s best scene, Gavin unloads his rage and remorse on a therapist sent by the city to help the men cope with their anger.

While “Rescue” is set in a New York fire station still raw from the losses of 9/11, it’s also clearly inspired by the star’s work with The Leary Firefighters Foundation, a charity dedicated to the memories of his cousin and a childhood friend killed in a 1999 Worcester, Mass., warehouse fire that claimed six firefighters.

Leary’s Gavin is also vintage Denis Leary, a caustic chain smoker who distills all of his pent-up feelings into a drive-by spray-down of high-caliber profanity. But this well-honed act, combined with the loaded emotional atmosphere of a post-9/11 firehouse, frequently threatens to go straight over the top.

• The two-hour documentary “1421: The Year China Discovered America” (8 p.m., PBS) examines the theory, put forth by researcher Gavin Menzies, that Chinese sailors circumnavigated the globe decades before Columbus, and even created maps that proved helpful to later European explorers.

Tonight’s other highlights

• Scheduled on “60 Minutes II” (7 p.m., CBS): Strom Thurmond’s daughter; designer Isaac Mizrahi; a teenage athlete’s suicide is linked to steroids.
• Scheduled on “48 Hours Investigates” (9 p.m., CBS): a wife stabbed her husband 193 times. What did he do to deserve that?
• Hey, couples, put your pens down! “The Ultimate Love Test” (9 p.m., ABC) is finally over.

Late night

Sharon Stone and Yeah Yeah Yeahs share a couch on “Late Show with David Letterman” (10:35 p.m., CBS) … Jay Leno hosts Big & Rich on “The Tonight Show” (10:35 p.m., NBC) … Sarah Wynter and George Benson appear on “Jimmy Kimmel Live” (11:05 p.m., ABC).