London befriends Howard Mattson, an elderly transport-truck driver who is
bitter about impending forced retirement at age of 65.
Despite London's disapproval, Mattson decides to confiscate the truck that he has driven for many years after he sees it stop for gasoline at Artie's Truck Stop.
What he does not know is that the truck has been rented by two bandits and contains a million dollars' worth of stolen furs.
The criminals see their rented truck being driven away from them and contact the trucking firm from which they rented it to inquire about who else has a key to the ignition, and they are given Mattson's name and address.
Mattson's plans to return the truck on the following morning are halted when he sees the stolen furs in its rear.
Fearful that the police will think that he was involved in the fur heist, Mattson does not immediately report what he has found.
While Mattson goes to the trucking firm to talk to the owner about the furs, the thieves kidnap Mattson's grandson, Daniel, and detain him to insure that Mattson brings the furs and truck to a rendezvous point of their choosing.
The crooks tie Mattson and Daniel to chairs in an isolated house, and when they go to the truck to check that the furs are inside, London jumps out of the truck, with a fur in his mouth, leading the criminals on a chase.
He returns to the truck, with the nefarious pair in pursuit, and locks them inside of it. Then, he frees Mattson and Daniel, and Mattson telephones the police, who reward him for recovering the furs and catching the thieves.