 Race-car driver "Burn- em-Up" Barnes (Jack Mulhall), adopts Bobbie Riley (Frankie Darro), the kid brother of his buddy George Riley (James Bush), who was killed in a race. Barnes enters into a partnership in a bus transportation business with Marjorie Temple (Lola Lane), whose life he saved in a battle with some gangsters. John Drummond (Jason Robards, who never once in his long film career was billed as Jason Robards, Sr.), a scheming promoter, knows that land Marjorie has inherited lies atop valuable oil deposits and tries every method to wreck her business and force her to sell the land at a low price. Barnes takes desperate chances to raise money and keep Marjorie from losing her property in spite of the attempts made on his life.This, like most of the Mascot serials, is very visually interesting because of the many outdoor scenes that depict the L.A. area of the time.