Harriet wears costumes everywhere—laundromat, park, dentist. When her dads take her shopping for her birthday party snacks, she’s dressed as a penguin and waddles off in search of party hats. “… don’t get carried away,” they tell her. Harriet does get carried away—literally—by a passel of penguins she meets in the frozen food aisle. “Where are we going?” It turns out the penguins are going back home, in hot air balloons. “I don’t think I belong here,” Harriet says when they arrive. An ice floe, an improvised parasail, an orca whale, and some city pigeons all aid in her return trip, and she nabs the last package of party hats on the rack. Harriet changes into her lion costume for the evening rooftop birthday party, which includes her diverse group of friends, each sporting costumes of their own. Layered visual storytelling in soft purple, blue, and gray chronicle biracial Harriet’s whimsical journey and warm, funny, realistic details of her life in the city with her dads (one Black, one white) in an affirming story that celebrates imagination. (Ages 3–6)