The work of Peter Ketley on Fisheries Research in Devon is being disorganised by a mysterious new method of salmon poaching. His young brother Bob, with the help of two children from London, eventually uncovers and catches the poachers.
Jeremy Bulloch
Bob Ketley
Joanna Horlock
Susan
James Luck
Simon
Anthony Parker
Peter Ketley
Larry Burns
George
Bruce Wightman
Tom
Michael Collins
Arnold
Lane Meddick
Mr. Atherton
Armine Sandford
Mrs. Atherton
Ben Williams
Quarryman
