After an exciting summer as a vacation worker in a hotel, life tends to run more normally. Tom continues to tinker with his inventions, Anna is training to be a photographer and Liv is eager but willful to pursue a career as an actress. But one day, a strangely dressed girl named Sandra shows up at Tom's door. It quickly turns out that the girl in the pink petticoat has traveled to the present with the time machine from Hotel 13. However, her appearance changes the past and with it the present and future. Tom, Anna and Liv must travel back in time with Sandra to keep the world from falling apart. Not only is Sandra's future with the movie star David at stake, but also the friendship of Tom, Anna and Liv.