Critiquing the plot of the new action series “Jonny Zero” (8 p.m., Fox) is a little like chastising water for being wet. “Jonny Zero” is ridiculous, and purposely so. Ex-con Jonny Calvo (Franky G) is a pastiche of a million other movie and TV characters. Free on parole, he hits the mean streets trying to go straight. But just a few steps from the prison fence he’s set upon by his old employers, who try to drag him back into “the life.” He runs away and begins the first of what seem like 50 chase scenes in the show’s first 40 minutes.

We quickly learn that Jonny is a former bouncer with a killer punch and a heart of, if not gold, then at least of zircon. Jonny is the kind of character Mickey Rourke used to play before he got too close to his “Barfly” persona. When Jonny walks down the street, every guy says, “Hey Jonny, how ya’ doin’?” and every girl casts steamy, come-hither glances in his direction. Despite or perhaps because of this magnetic heat, Jonny gets into a fistfight every five minutes.

Jonny quickly teams up with Random (GQ), a self-professed Renaissance man and professional DJ who’s squatting in an abandoned building by the side of the river. Random plays the fool to Jonny’s King Lear, rhyming and rapping even in the face of gunfire. And, for reasons and motivations never clearly explained, Jonny tries to rescue a wayward stripper (Brennan Hesser) with a confusing background.

If this weren’t exciting enough, FBI agents try to recruit Jonny to infiltrate the mobbed-up and nefarious club scene that used to be his private little pond. As discussed, the plot is paper thin and frequently preposterous, but it all provides an excuse for Jonny and his odd entourage to saunter into bars and clubs of every deviant stripe, and for viewers to see girls and boys in exotic states of dress and undress. The music is loud, the pacing is furious and, every five minutes or so, fists and bullets fly.

Tonight’s other highlights

• God casts Joan in the school musical on “Joan of Arcadia” (7 p.m., CBS).
• On back-to-back episodes of “Bernie Mac” (Fox), total exposure (7 p.m.), wedding woes (7:30 p.m.).
• Sullivan’s trial proceeds on “Third Watch” (8 p.m., NBC).
• After seven years and 2 billion miles, the Cassini-Huygens Saturn probe lands on Titan, the largest moon of the ringed planet, on “Touchdown on Saturn’s Moon” (8 p.m., Discovery Science).
• Scheduled on “20/20” (9 p.m., ABC): an interview with President George W. Bush and first lady Laura Bush.