Albert, a jockey, is upset that Thunderhead, his favorite horse, may soon be retired by the stable`s owner and put out to stud. He sees a chance to revive Thunderhead`s career when Runaway, one of the owner`s best horses, injures a leg before he is to be sent to a race in France. Albert plans to replace Runaway with Thunderhead and ride him in the race. However, thanks to two crooked stable employees, things don`t turn out quite as planned.