Fifth grader Amy Prochenko is wildly unpopular. Then one day Amy meets Sherlock, a dog on the run from a university lab. Sherlock is not like other dogs: He can talk, he's smarter than most of Amy's classmates - and he needs Amy's help. Suddenly Amy's life is full of danger and excitement, and she finds she is becoming, of all things, "popular." Best of all, she discovers in Sherlock the sort of friend she's always longed for - one she must protect no matter what the cost.