Jesse Tyler Ferguson, Eric Stonestreet

Modern Family is heading to Sin City.

After Jay (Ed O'Neill) and Gloria (Sofia Vergara) get some upgraded rooms at a hotel on Wednesday's episode, they decide to bring the entire Pritchett-Dunphy clan with them to Las Vegas — which would be the perfect setting for Mitch (Jesse Tyler Ferguson) and Cam's (Eric Stonestreet) bachelor party, right?! Eh, not so much.

"We go there for kind of an anti-bachelor party," Stonestreet tells TVGuide.com. "Claire (Julie Bowen) wants to make it our bachelor party but we just sort of are like, 'No, we're 40, we have a baby, we've been together 10 years. We're not having a bachelor party.'"

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But Cam starts to rethink their stance after running into friends who are doing a joint bachelor party. (Look for Fred Armisen in a hilarious cameo as one-half of the couple, who also happens to be an ex of Mitch's.) "[Cam], unbeknownst to Mitch, starts sneaking off and going to different aspects of their bachelor party while [Mitch] is getting a massage, while he's in the sauna, that kind of stuff," Stonestreet teases.

Also guest-starring in the episode are Patton Oswalt, playing the head of a group of magicians Phil (Ty Burrell) is trying to join, and Stephen Merchant, playing an extremely accommodating butler. Check out a sneak peek from "Las Vegas" below:

Modern Family airs Wednesdays at 9/8c on ABC.