When young reporter and amateur biker Jerry Marsh investigates a mysterious hooded figure on a motorbike, he discovers crooks hiding out in a ruined castle with atomic sabotage on their minds...

A woman reporter discovers a former lover and intelligence officer during WWII apparently working as a waiter in a hotel; and, believing something she impulsively did while he was on a mission is responsible for his current situation, sets out to make things better by finding a foreign agent known only as Kupchek, with the help of the hotel's detective.

Katie attempts to save her father's failing garage, after he is killed during a stock car race. She is assisted by an American driver, Larry Duke, but unfortunately one of the creditors is determined to take the garage.