Adam Joshua finds that Valentine's Day is ``a whole lot scarier'' than Halloween. Just as longtime best buddy Nelson develops a baffling crush on classmate Heidi, Adam Joshua's good old dog George begins to run off with Lucy, the new dog on the block. Then he learns that his name has been omitted from the Secret Friends exchange, but he's getting notes and candy anyway. Adam Joshua has a lot of worries and no one to talk to, since George has always been his closest confidant. Events culminate on Valentine's Day, beginning with Nelson's innocent gift to Heidi: a goldfish, which she detests so much that she vows revenge on the unknown perpetrator. Then Adam Joshua's suspicions are confirmed when he discovers that Heidi has been his unauthorized Secret Friend. In a selfless, courageous moment, Adam Joshua acts on Nelson's behalf, with a move that will have readers shrieking with delight. Recalling Frog and Toad's loyal friendship, this funny, endearing story is a welcome addition for transitional readers at Valentine's Day. One of Smith's best. (Fiction. 6-9)