At the start of the 1920 baseball season, 16-year-old Hank Cobb is assigned to train the New York Giants' new mascot, a Mexican wildcat named Bill Pennant. Bill's not too trainable, though, even with the help of sardines and mice. And if Hank can't handle a cat, how can he handle his next charge, an undisciplined slugger for the Yankees named Babe Ruth? Ruth's manager asks Hank to keep an eye on Ruth, and since both teams play at the same stadium, it's doable. But is it wise? A disastrous "road trip" to Coney Island lands both Babe and Hank in hot water with their respective managers. Hank, who's fallen under Babe's spell, walks out on the Giants, determined to ditch school and become a big-league ballplayer. But another, far more serious incident, causes Hank to rethink his priorities. Evocative descriptions of the sights, sounds, and personalities of baseball's heyday add to this exciting story about loyalty, responsibility, and the rules of the game -- both on and off the field.