As anyone who has been watching “Project Runway” (9 p.m., Bravo) already knows, something terrible is supposed to happen tonight, an action so heinous and rule-breaking it will result in the sudden expulsion of a participant.

At least I hope it happens tonight. They’ve shown a teaser reel of the terrible moment approximately 80,000 times.

Now in its third season, “Runway” is still going strong and provides proof that reality shows are all in the casting. While this show is not without contrived tension and brittle drama, its reliance on spontaneous creativity and a ticking clock keeps it interesting. Make that fascinating, entertaining and fun.

This year’s contestants also seem more mature, more sure of themselves and their talents and less prone to emotional breakdowns. Contrast this to “America’s Next Top Model” (7 p.m., UPN), where Tyra and her entourage seem to be babysitting overgrown adolescents and corralling their raging hormones.

This season’s “Runway” features Laura, a 42-year-old mother of five, and Vince, 49, a quirky personality who appears to have taken his adolescence and fashion sense out of mothballs after a long hiatus. If Vincent were a fictional comic character, he would be played by Rick Moranis imitating Woody Allen.

The continued appeal of “Runway” also owes much to host Heidi Klum’s very conscious decision to share the spotlight and reign as first among equals. If anyone has emerged as a “star,” it’s Tim Gunn, the Parsons School of Design chairman who offers avuncular and slightly world-weary advice to the designers. A raised eyebrow from Gunn can cause panic.

And while it has its share of name-brand items, “Runway” appears to be immune to the ludicrous tsunami of product placements that drowned “The Apprentice” after its first hit season. “Runway” did play nice with its corporate cousins a few weeks back, helping to hype the Miss Universe pageant by designing a dress for Miss USA and allowing the daughter of the pageant’s owner, Donald Trump (who also hosts NBC’s “The Apprentice”), to appear as a guest judge. But so far, “Runway” continues to rise above such nonsense. It appears to be a show that not even NBC Universal can destroy.

Tonight’s other highlights

¢ Regis Philbin hosts “America’s Got Talent” (7 p.m., NBC).

¢ A heart patient has an allergic reaction to a “clean” room on “House” (7 p.m., Fox).

¢ A half dozen put 12 feet forward on “So You Think You Can Dance” (8 p.m., Fox).

¢ Slain teens raise fears of a thrill-kill cult on “Criminal Minds” (8 p.m., CBS).

¢ Sayid discovers another “other” on “Lost” (8 p.m., ABC).

¢ Two episodes of “Nightmares & Dreamscapes” (TNT) feature performances by Richard Thomas and Greta Scacchi (8 p.m.) and Kim Delaney and Steven Weber (9 p.m.).

¢ Are shark attacks on the rise or merely a phenomenon of summer media? Find out on “Sharks: Are They Hunting Us?” (8 p.m., Discovery).

¢ Murder rocks the rock world on “CSI: NY” (9 p.m., CBS).

¢ A leak may have resulted in an officer’s murder on “Law & Order” (9 p.m., NBC).