Twelve-year-old Mira's summer is looking pretty bleak. Her best friend Thomas just moved a billion and one miles away from Florida to Washington, DC. Her dad is job searching and he's been super down lately. Her phone screen cracked after a home science experiment gone wrong. And of all people who could have moved into Thomas's old house down the street, Mira gets stuck with Tamika Smith, her know-it-all nemesis who's kept Mira in second place at the school science fair four years running.

Mira's beloved cat, Sir Fig Newton, has been the most stable thing in her life lately, but now he seems off, too. With her phone gone and no internet over the weekend at her strict Gran's house, Mira must research Fig's symptoms the old-fashioned way: at the library. She determines that he has "the silent cat killer" diabetes. A visit to the vet confirms her diagnosis, but that one appointment stretched family funds to the limit--they'll never be able to afford cat insulin shots.

When Mira's parents tell her they may have to give Fig up to people who can afford his treatment, Mira insists she can earn the $2,000 needed within a month. Armed with ingenuity, determination, and one surprising ally, can Mira save her best (four-legged) friend before it's too late?