"Mira and her unicorn, Dave, tackle their greatest challenge yet: teamwork. Mira is excited for Unicorn School Field Day, even though her unicorn, Dave, loves donuts more than prancing. Mira's teammates are counting on them-especially when the prize for winning Field Day is revealed to be the chance to go on a Magical Rainbow Quest. As Mira struggles to get her UBFF (Unicorn Best Friend Forever) to hurry to the finish line, a series of mysterious mishaps make Mira wonder if everyone is playing fair. Can she and Dave track down who's sabotaging them before they end up in last place?"--Back cover.