Ann and Chris are both busy prepping their respective bachelorette and bachelor parties for the bride and groom-to-be! The night should be a crazy one for the girls: dancing, Jell-O shots and anything that can be penis shaped, will be penis shaped. The guys, on the other hand, have a more low-key night in store; Ben's idea of a good time is beer and board games. Literally.
The guys indulge Ben in a game of Settlers of Catan, which he unsurprisingly wins (it wasn't a fair fight really, he's nationally ranked). But as the game comes to a close, Tom finally reaches his breaking point. He can't just let a bachelor party peter out like this! Tom suggests that the guys pay a visit to Eagleton's hot new bar, Essence, which specializes in "molecular mixology." Ron is understandably horrified when his whiskey is served in lotion form (you can also order vodka as a flash of light!). The guys get to talking and quickly realize than NONE of them had bachelor parties before their weddings! Chris declares that tonight, everyone gets their own bachelor party experience.
Meanwhile, at the bachelorette party, all of Ann's diligent planning seems to be going to waste. Leslie discovers that Councilman Jamm is moving forward with their plans to turn the infamous lot into a Paunch Burger. After years of work and planning, her hope to turn the lot into a park is ruined! Leslie contrives a plan to get revenge, littering the pit with what she hopes will pass as sacred Wamapoke artifacts, and thus halt all construction on the lot. But the second she does, she realizes she's made a horrible mistake. She confesses her mess to the girls and recruits them to help her fix it.
For the next stop of the bachelor party adventure, the guys pay a visit to Jerry's favorite ice cream parlor, where he first met Gail. After raising a cone to Jerry, they talk about Andy's dream plans, which include a Colts game. Coincidentally enough, Chris can make that dream happen! Chris and Colts owner Jim Ersay became friends when they mentored Indianapolis teens. The guys pay a visit to the stadium, and Andy catches a touchdown pass from none other than Andrew Luck. The guys wrap up their adventure with a visit to one of Ron's favorite joints, St. Elmo's Steak House.
The bachelorette party spends all night digging in what turns out to be a miserable night. To add insult to injury, their efforts were for nothing – as supposed artifacts are found at the site the next day. They later meet with Chief Hotate of the Wamapoke tribe, and Leslie privately confesses to him what she did. It's clear that Leslie's truly sorry, but her damage may be irreparable.
The bachelor party was such a great night! But the guys only wish that there was some way they could show Chris just how much they appreciated his efforts. They buy Chris a "Best Best Man" trophy and reassure him that someday he'll meet the perfect girl for him, who's a super fit health goddess. But Chris surprises the guys, saying that someone who shares all of his interests may not be what he's looking for anymore. All he really needs is someone who values happiness and friendship. This inspires Ben to set up Chris with the reporter Shauna Malwae-Tweep, who's excited to write a story on Chris' bachelor party adventure.
While meeting with Councilman Jamm and Leslie, Chief Hotate says that artifacts in fact were not legitimate. But before he lets Leslie confess, he pulls a surprising move, telling Jamm that he didn't like the way he went back on his word with Leslie, as it reminds him of the way the settlers treated his ancestors. There are six Paunch Burgers in the Wamapoke Casino; perhaps it's time they revisited those contracts. This scares Jamm straight, and he agrees to put aside construction on the Paunch Burger for now.