It's the end of summer, & Seth convinces a reluctant Ryan to plan a trip to Tijuana, where hundreds of rowdy teens congregate to indulge in escapist excess before they have to begin school again. In addition to dating Luke again, Marissa is angry with Ryan after witnessing him with an older woman. She also wants to stay home & take care of her overstressed father. But Summer persuades her to come, & the four kids drive south, Ryan & Marissa not speaking to each other & Summer & Seth sparring constantly. During an argument, Seth accidentally drives off the road & damages the car. The friends are forced to stay in a disgusting motel overnight while the car is being repaired.