In the line for Marriage Can Be Murder, the audience participation begins before the crowd has even made its way inside the showroom. Tasked with taking everyone’s food orders for the dinner show, a maître d’ who says his name is Sal, dressed in a loud sport coat that matches his loud voice, instructs everyone in line to yell “Hi, Sal!” at him each time he introduces himself. There are a lot of chants of “Hi, Sal!” by the time everyone is seated, ready to take part in an interactive comedic murder mystery.

Is Sal a killer? What about the evening’s host, a ditzy blonde named Birdie? How about the burly police officer who barges into the theater to solve the evening’s first murder? Everyone’s a suspect in this lively, goofy show, and that includes the patrons. You might be called on to provide testimony to that officer (who’s wearing some uncomfortably tight shorts), or you might be accused of being a potential murderer yourself. It’s all part of the charm for Marriage Can Be Murder, which has been going strong for 19 years in Las Vegas, making it the longest-running dinner show in town.

Although there’s now an option to play along on Facebook during the show, solving the mystery still relies on jotting down clues and theories via old-fashioned pen and paper. Turn in your answers at the end of the show, and you could win the “super sleuth” prize if you manage to get the details right. Or just play along with the silliness, and you might win a prize for “best supporting actor/actress.” Either way, the show thrives on participation, and the unique combination of audience members makes each performance a one-of-a-kind experience.

The D, 6:30 p.m. daily, $71.95-$101.95 plus tax and fee, includes three-course meal and show. 702.388.2111