Cat and Alex are excited to be at the world’s largest comics convention—and they’re even more excited to compete in the Quest, a huge scavenger hunt run by an anonymous organizer. The big prize: a chance to meet their favorite nerdy celebrity! The twins ditch their older sister Fiona and set off to find geeky clues, tackle nerdy challenges, and cross as many items as possible off their Quest list, which includes: volunteering at an Artist Alley booth, gathering cosplayers in enough colors to make a double rainbow, and even finding something healthy to eat in the convention center!

Can Cat and Alex work together even when they disagree on how to compete? Will Fiona find the twins before their parents realize they’re missing? Most importantly, can these ultimate fans complete the Quest?