Jim Pennell is working in a marine reasearch project on an island off Tanganyika (as it was still called then). He encounters two people, Martin Gage and Sandra Nelson, survivors from a small plane that has ditched in the sea close to the island. A third member of the group, Bob Dewer, has apparently perished in the crash. Gage carries a suitcase which he guards carefully. Indeed he will stop at nothing to guard that suitcase. What is he carrying? (The title might help you guess.)
Canning re-used a plot idea from this story in his 1967 novel The Python Project.John Bull, 22 March, 1958.
Included in the collection The Exotics, ed. John Higgins.