Hammer the Toff plot
On a trip to the seaside town of Brighthaven, Richard Rollison shares a train compartment with the attractive Susan Lancaster. But then the train window is shattered by bullets. Richard hears from Susan that she is on her way to an uncle and offers to take her safely to her hotel. Her uncle appears to have disappeared, but has left a package for Susan. Later, Rollison overhears some strangers talking about kidnapping Susan. Susan tells that her uncle has developed a secret formula. Rollison consults his old colleague Inspector Grice from Scotland Yard, who tells him that the evidence points to a kidnapping. And then Susan is kidnapped.