Gail and Tom Hartman are struggling to stay together and decide to take a white-water rafting holiday adventure in Montana for their son Roarke's 10th birthday, only to meet up with a pair of mysterious men whose desperation grows, turning their vacation into a nightmare.

George is an uptight surgeon with a rebellious teenage son. Edith is a free spirit with an overachieving teenage daughter. When they meet during an admissions tour with their kids at the small, idyllic Middleton University, they decide to ditch the group. Though adversaries at first, they soon discover that the only thing better than the college tour, is the detour.

Suk-hee's mother is remarried to a man who has a son a year senior than Suk-hee. The two don't get along well first, but soon they grow intimate. Suk-hee learns, though, that she needs to give up her love for her mother's happiness. One day she leaves her mother and her new family, and goes on her way to her hometown, where she sees a Zelkova tree.

Unforeseen obstacles stand in the way of a family planning to take a road trip in an RV.