Buzz is not happy to hear that he's grounded for a month after getting drunk at his illicit 16th birthday party, stealing Roger's ATV and driving it into the lake. Cole offers to kick Buzz's ass, but Mack tells him to stand down. What Cole really wants to know is whether Mack has considered his offer of a relationship? For now, she prefers to pretend like it never happened. Cole isn't bothered; Mack can take her time because he's not going anywhere. Sarah's enjoying a romantic morning in bed with Miguel when she realizes she's late for work. Roger spies her on the way home. Why is Sarah flushed, sweaty and on the wrong side of the lake? She must have been using Camp Ridgefield's gym.
At breakfast, Mack announces that the CITs' parents are expected for Parents' Weekend, a camp tradition. Kip's dad is first to arrive, and he wastes no time embarrassing his son, announcing that he's a "twitcher," aka a bird-watcher. Her affection for Greg having cooled, Marina is just telling him that her mother can't make the weekend, when a near-hysterical woman drags an enormous suitcase into the dining hall - Marina's mother Crystal. It turns out Crystal's bodybuilding boyfriend has left her, making Crystal and Marina homeless.
Grace's eyes go wide, watching a shirtless Robbie helping Cole work on his new/old motorcycle. It needs a new engine, which means Cole needs $1,000, and Robbie only has a few hundred to lend. It's not long before Crystal is deep into a box of Chablis, and Mack stops by to invite mother and daughter on a nature hike - not really Crystal's cup of tea. Mack is amassing the hikers when Bethany storms up, demanding to know what happened to her daughter Zoe's hair. She's going to miss pageant season and she looks awful! Zoe takes notice when Buzz comes to her defense, declaring that she's beautiful just the way she is.
Kip's dad Larry wants to know what's really been happening in his son's life at camp. When Marina and her mom pass by, Larry recognizes the look of a man in love, which is when Chloe introduces herself as Kip's girlfriend. Cole rescues Mack from Bethany's clutches, doing his best to be her hero, and gets the hike started. A little tipsy, Crystal trips. Bethany's husband Ken rescues her, earning the side-eye from his wife. Cole has Kip give a nature speech, further impressing Larry, while Buzz scores points with Chloe, thanking her for not ratting out Marina over the haircut and assessing her mom as a total bitch. Chloe agrees that Bethany doesn't like Buzz, but Chloe is starting to revise her own opinion of him...
The hike stops on a massive bluff over a creek, otherwise known as the Steele Creek Rock Jump. When Mack asks for volunteers, Crystal is the first one over the side and Marina quickly follows. Kip is ready to go with Cole, but Larry holds him back; why take a chance when Kip just got into remission? That night, all the adults who can drink hang out at the local bar. Kip is just telling Sarah he misses her since they haven't seen each other all week, when Miguel walks in with a beautiful woman. Roiling with jealousy, Sarah mumbles that her coach is making her practice swimming all the time.
Cole runs into Roger and his darts partner Phil, and the trash talking is on. When Roger challenges Cole to enter that week's dart tournament, Cole considers. He may not have a partner, but if he wins the tournament, Roger will pay him $1,000; if he loses, he'll work at Camp Ridgefield for free for one week. Sarah corners Miguel in the bathroom. She knows she has no right, but she's jealous - and it's over. Just then Phil pops out of a stall and leaves in a hurry. Miguel explains that the woman is his book agent, and she's loving the rough draft of his latest novel; so he has to move back to New York on Sunday. Miguel invites her to have dinner in his cabin so they can say a proper good-bye.
Back at the camp, Mack is drinking with Raffi, Todd and Sheila, and they're bitching at the other parents - who are worse than the kids. It's Movie Night, and Larry can't contain his enthusiasm for how well Kip is doing at camp. Does Kip have any questions about sexual intercourse? Kip is even more embarrassed when his dad girts him with a pair of binoculars, which they can use to go bird-watching. Meanwhile, Marina's mom is deep into her second box of wine and flirting with Greg, hard. Marina admits she's thinking Greg's kind of dumb, and furthermore, Crystal doesn't need a man in her life. What if they started over, just the two of them? The girls clink their glasses over a newly hatched plan to move to Florida.
The next morning, a sober Sarah confesses to Mack that she cheated on Robbie. Does Mack wish she never found out about Steve's affair? Mack allows that her situation is totally different from Sarah's, but one thing's for sure: an affair changes everything forever. If the affair is really over, then it's all about what Sarah can live with. Cole asks Kip to be his partner in the dart tournament, which is happening at the bar this afternoon. Kip is flattered to be asked, but his dad isn't pleased when he begs out of bird-watching. Before long, father and son are arguing. Larry says that he wants Kip to experience everything the camp has to offer, but when it comes down to it, all he wants to do is watch birds, which sucks.
Chloe approaches Marina - when's the last time she saw Crystal or Zoe's dad? In a panic, both girls race off to find their parents. They arrive just in time to see Bethany slapping her husband. Chloe tells Marina not to let her slutty mom believe a word Ken says. But it's too late; Crystal has big news. Ken offered her a secretarial job in Denver! The move to Florida is off. Marina lays into Crystal, who has always treated her like an adult. Marina claims it's no surprise she lost her virginity at 13, considering she has a slut for a mom. Later, Buzz finds Chloe crying in Toddler Town. After bonding over cheating parents, they start making out. Then Chloe offers the holy grail: Buzz needs to come to her cabin in 20 minutes, alone.
Surprised to find Cole's dart tournament partner is Kip, Roger offers to double their wager. The pressure's on, but Kip is acing it. Cole points out that Sarah didn't show up, even though she's got $50 riding on the winner. Robbie has no idea that Sarah has just knocked on Miguel's door... Mack has just noticed Buzz has left Toddler Town unattended when Bethany stomps up. She's leaving the camp and can't find Chloe anywhere! Buzz is just about to get to second base when Mack and Bethany stomp into his cabin. Buzz does his best to hide Chloe, but he's just no match for Mack, who finds her hiding under the bed covers with no shirt on.
Kip and Cole make it the final round of the dart tournament, playing against Roger and Steve. Looking queasy, Kip excuses himself to go to the bathroom on a break, where he starts vomiting blood. Roger mentions that he keeps catching Sarah using his gym, and Steven advises Robbie to get over to Camp Ridgefield, where unbeknownst to anyone, a romantic good-bye dinner is underway. When Miguel invites Sarah to come to New York with him, there's a knock at the door. Miguel thinks it's room service - but it's Robbie. Sarah breaks into tears and runs after Robbie. The affair only lasted a week, and she was just saying goodbye! Robbie doesn't care; he doesn't want to know Sarah anymore.
It's the last round of the dart tournament, and Kip has to score an 18, a 19 and a bull's eye to win it all. Kip feels sick but Cole tells him it's just jitters. Kip pulls it together to win the game, then collapses, telling Cole he needs his dad. Back at the camp, Buzz and Chloe are in tears as Bethany loads her daughter into the car and drives off. When Mack asks how Buzz could leave Toddler Town in the hands of a random CIT, he tries to explain that it was a once in a lifetime opportunity. Furious, Mack tells Buzz that she's going to recalibrate her expectations, based on all the dumb stuff coming out of his mouth. Just then, Larry comes running outside with news that Kip is sick and in a bar. Mack offers to drive, and Buzz insists on coming.
Moments later, several cars are making the long drive to the hospital as Larry cradles Kip in his lap. Kip is convinced his cancer is back, and it's not long before the news reaches the camp. Knowing Marina cares a lot for Kip, Crystal offers to drive her to the hospital. As Kip is wheeled into the emergency room, Mack lays into Cole for bringing Kip to a bar - she shouldn't have to explain this to him! Cole waits by the door for Larry, hoping for news about Kip. But when Larry finally emerges, all he does is throw Cole against the wall.
In the waiting room, Crystal and Marina have a heart-to-heart. Crystal knows she always goes after the wrong men, and Marina fears she's turning out just like her mom. Crystal assures Marina that she's far more confident and smart than Crystal ever was. They say you pick the people you deserve, and Marina deserves someone really special. Roger tells Mack that his sister had leukemia when they were kids; so he knows the drill, and he thinks about his sister every day. Finally, the doctor comes back with the results - Kip has food poisoning! He's going to be fine. Buzz and Marina run in to see their friend. Early the next day, Kip and Larry take an epic jump off Steele Creek Rock. Life is great!