Con artist and racetrack tout Wally Brooks hands a lemon drop to a man in a wheelchair, saying it will cure whatever ails him, then persuades the man, a millionaire named Griggsby, to bet $100 on a horse. Wally knows this horse can't win and intends to pocket the cash. The horse does win, so Wally and his partner Dunhill, alias "The Professor," take it on the lam.