
John Corby is birdwatching with his father Tom. Susan Fraser has found herself cut off from land so John helps her. Reaching land, she gives him a note to explain his absence to his father. However, nobody seems to know where Tom has gone.
John and Susan seek police help to look for Tom. The police won't intervene, as Tom Corby is suspended from Scotland Yard. Tom and his two contacts meet up with Kessler. Police surveillance believe Corby is on the take.