It's Lindsay's birthday and trouble's a brewing when Carl brings girls to the party, much to Lauren's dismay. Everett and Lindsay are on the outs, and Stephen spills a secret that may make the "on and off" again couple turn the switch off permanently.

The roommates go from blowing out candles for Kyle's birthday surprise to a blowout fight that derails everyone's good time and leave Lindsay and Everett on the brink of a breakup. Meanwhile, at Model Volleyball, Cristina serves up some juicy gossip that Jaclyn hasn't been a model friend to Lauren. And at long last, the Wirkus parents meet the infamous Carl.

With a scandalous secret looming over Lindsay and Everett's relationship, the pressure is on for the power couple to sink or swim. The roommates must come together to throw a race for charity, but not everyone will make it out in one piece. And finally, Cristina's meddling catches up to her when Lauren and Jaclyn go on the attack.

It's time for the annual Rosé Party, where Kyle meets a fellow blonde who may or may not be his drunken soul mate. It's Cristina vs everyone else, as the roommates take aim at her meddling ways.

Summer's over, and that means one last wild weekend with no regrets...or maybe a few. A Hamptons White Party turns into a messy affair when Kyle blows up at his ex-girlfriend Amanda over a lip-syncing scandal. Meanwhile, Cristina makes a dramatic exit, and Carl and Lauren's romantic pretzel twists one final time, when Carl disappears into the night.

When the roommates go to a winery there is more "whine" than wine. As the drama between Lindsay and Cristina reaches its breaking point, someone may be evicted. Carl cools off on Lauren but warms up to Jaclyn at a beach bonfire.

Kyle confronts "perfect couple" Everett and Lindsay for disrupting his "single" summer. New house guest Jaclyn raises eyebrows with her Southern sensibility...or lack thereof. Carl gets caught in a lie that threatens his new relationship with Lauren.

Lauren confronts Carl for lying about bringing a date to a wedding. Kyle dips his toe back into the ex-pool, despite everyone's warnings. Lindsay and Cristina's roommate drama boils over into full-on name calling and accusations.

There are fireworks on Independence Day; Lauren and Carl's relationship heats up in the bedroom; Kyle juggles two women at a party; love birds Everett and Lindsay's explosive antics prove they're anything but the perfect couple.

A group of New Yorkers rent a summerhouse in Montauk, N.Y.; Ashley and Lauren extend an invitation to their friend, Stassi, who sets her sights on Kyle; longtime friends Everett and Lindsay become intimate; new guy Carl plays the field.