Eleven-year-old Darcy just moved to a new country, and she misses her life back home. When she stumbles upon a shop full of mysterious glowing jars labeled with things like "Picking up the last sweater on the rack and it's on sale" and "Having the perfect weather on your wedding day," she discovers the store sells happy feelings. After Darcy accidentally breaks one of the irreplaceable jars, she must make it up to the shopkeepers, Frida and Flora, by doing chores around the store, and is soon tasked with collecting happy feelings. But when Darcy learns that the store is struggling financially, she wonders if there's a way to save the shop using more than just happy feelings.