Stephen thinks he has to teach Kirstin how to surf, something she doesn't really like. Kirstin plans to cook with Jessica for Dieter and Stephen - a difficult project, when nobody knows how to cook! Stephen is getting jealous and he wants to talk with her at the bonfire - what will she say?

When LC, Stephen and Trey check out a designer fashion show in LA, LC watches Stephen's attention turn from fashion to fashion models. Meanwhile in Laguna, Kristin, Alex, and Sam, a junior hottie, go look at expensive cars, but Kristin's day of joyriding comes to a surprisingly abrupt halt, causing a nightmare no one expected.

When Morgan throws Christina an 18th-birthday bash, she cuts LC and Lo from the guest list, so bumping into them the next day at the nail salon was sweet irony. Christina and Morgan then head to NYC for their spring break trip. While Morgan soaks in the big city fashion, Christina is challenged by the audition of a lifetime.

It's spring break in Cabo and anything can happen, especially since LC, Stephen and Kristin are staying in the same hotel. Kristin's wild partying at a club prompts a fight with Stephen, opening the door for him to hook back up with LC.

Spring Break is over and everyone has to deal with the past events. For distraction everyone has the Blink 182 concert in mind. Some organise their very own fashion show, while others plan a romantic dinner.

It's prom time, and while everyone is caught up with who's going with whom, which pair of Charles David shoes look best with their dress, and how to fit everyone in the stretch Hummer limo, Kristin's biggest concern is a drama-free night with Stephen. She’s confident it will be… as long as LC keeps her distance.

The seniors charter a yacht to Catalina, but Lo skips out, leaving LC without a buddy to survive camping, kayaking, and Stephen and Kristin's incessant cuddling. Back in Laguna, Christina gives her first performance since the New York audition, from her father's renowned Crystal Cathedral.

Graduation day is here and the seniors spend time with their families getting ready for the big event. Through a Senior Video Project, the seniors reveal their personal thoughts on graduation, senior year, and life after Laguna.

Free from school, the gang lives up their last summer together, but when they gather for a final barbeque at Trey's house, the reality of leaving Laguna and each other starts to sink in.

In the final days before leaving Laguna, Stephen must tie up loose ends, first saying goodbye to Trey, then the surf shop and finally Kristin. Luckily there's one person he won’t have to part with.