The superstar a cappella group Pentatonix is struggling to find inspiration for their annual holiday album, and time is running out. To make matters worse, their well-meaning but misguided manager accidentally locks them in a magical post office. But with the help of some magical moments from Disney, we soon find ourselves on a lightning tour around the world, discovering holiday traditions and inspiration from Pentatonix fans across the globe: from Tokyo to Grenada, from Ghana to Mexico and Iceland.