Thunder Point is a novel in the Sean Dillon series by Jack Higgins, published in 1993.

Amateur diver Henry Baker goes diving in the Caribbean, where he finds the wreck of a German U-boat.

His inability to read German frustrates him but one name leaps out at him: Martin Bormann.

His next move is to go to England to see his friend, German speaker and Royal Navy man Garth Travers.

Travers translates the documents and can't believe what he's found - information on Nazi sympathizers in the United Kingdom and America.

He gets in touch with an old friend of his, Brigadier Charles Ferguson, who works for the Prime Minister.

The Prime Minister asks them to come to his office and invites two other men, Simon Carter and Sir Francis Pamer.

After their meeting with the Prime Minister, they decide to ask Baker about the location of the submarine.

Pamer discovers from his mother that his father had connections with the fascists during the Second World War.

The men plant a bug on the phone before they leave (against the wishes of their boss Santiago).

Ferguson is suspicious and asks his assistant inspector Jack Lane to check for bugs in the house.

They meet with Ferguson and she tells him what she knows but reveals that doesn't include the location of the submarine.

An IRA gunman and expert diver, Sean Dillon, is in prison in Yugoslavia.

Ferguson takes Dillon to meet Simon Carter and Francis Pamer.

Jenny is in bed in France when she wakes up and it occurs to her that she might be able to tell Dillon how to find the submarine.

Ferguson and Dillon are talking to Carney in a bar when they get into a fight with Santiago's men.

Ferguson gets a phone call from London, he discovers Inspector Lane is dead.

Alvaro then tries to rape her, in order to protect herself she jumps through the balcony door on the street.

[1] Thunder Point was adapted into a 1998 British-Canadian television thriller film directed by George Mihalka and starring Kyle MacLachlan as Sean Dillon, Pascale Bussières as Jenny Baker, Chris Wiggins as Sir Charles Ferguson, and Cedric Smith as Henry Baker.