David Collier is called urgently to Cyprus. He is soon involved with the mysterious and beautiful Helene who gives him disturbing news.
Collier's attempt to take Helene's evidence to Inspector Dimas is violently interrupted and he is unable to persuade the Inspector of the truth of what has happened. Later a meeting with his brother's friend, Eric Morrison, is broken up in a frightening way.
Collier stumbles on people he is sure can help him convince Inspector Dimas of his brother's murder. Later the evidence which Helene first produced mysteriously turns up again - and again leads to trouble.
After his violent clash with Collier, Morrison soon finds himself in a desperate situation. Hellman begins to show his hand - and Collier again meets Helene.
Collier unwittingly plays into the hands of Hellman. Meantime, from his hiding place, Morrison arranges to meet a buyer - but the deal goes sadly awry.
Morrison waits to conclude his deal - but he is horrified when the 'buyer' appears. Inspector Dimas is intrigued by what he learns from Collier; later he gets startling news from Morrison's girlfriend.
Preece is badly shaken by the things Hellman tells him. He realises he still has a long way to go to achieve his ends. Collier again meets Helene. Unsuspecting they wander into a situation of great danger.
Collier goes through a final shattering experience. Later inspector Dimas shows him something which Collier finds incredible, but which could offer an explanation for all that has happened.