- "The Chinese have a saying: 'Before setting out on revenge, you first dig two graves'."
- ― James Bond to Melina Havelock
In the film, Melina Havelock is half Greek, half British. She is the only daughter of Iona and Sir Timothy Havelock, two operatives working for the British Secret Service. Their mission takes them to the coast of Albania and Greece to look for a sunken British spy ship that holds a piece of equipment known as ATAC (Automatic Targeting and Attack Communicator). Melina comes to visit them and is witness to their brutal assassination by Hector Gonzales, a Cuban hitman.
Swearing revenge, Melina tracks Gonzales down to a villa outside of Madrid with the help of a private detective agency. There, she assassinates Gonzales by shooting him with a crossbow as he is diving into his swimming pool, but is only able to escape (in her Citroën 2CV hire car) with the help of James Bond, who was also there to investigate Havelock's murder. Having seen a man (Emile Locque) paying Gonzales, she vows her quest for vengeance must go on, though Bond tries to warn her off.
Melina travels to Cortina when she is sent a fake telegram telling her Bond has met her parents killer and to meet him in Cortina. Melina has a lucky escape when Bond notices her, and stops her getting run over by a couple of Yamaha motorcycles. He eventually persuades Melina to go back to the Triana in Corfu and let him investigate. She agrees to do so, but not for long.
After Bond kills Locque, he heads back to the Triana where he finds Melina clearing the seabed working on a Temple her father was restoring. After looking through her father's logs, Melina tells Bond about a wreck that her father, Sir Timothy Havelock, had located.
Bond and Melina travel underwater to a depth well over 500 metres in their two man submarine Neptune, to this wreck, the St. Georges. During the disarming of the ATAC aboard the St. Georges, Melina's air hose is ruptured during a fight with a man in a JIM diving suit. Melina rushes back to the boat whilst Bond takes care of the impostor.
After dealing with a Mantis submarine sent by Aristotle Kristatos, who had previously employed Gonzales to kill the Havelocks for him, Bond and Melina return to the surface. Back on board the Triana, Kristatos is waiting and relieves them of the ATAC. After escaping from Kristatos in a unique underwater sequence, they head with Milos Columbo to Kristatos' mountain retreat where he is hiding and recover the ATAC.
After finally catching Kristatos, Melina insists on killing him, but Bond tries to stop her, telling her that she would be no better than Kristatos if she killed him. The decision proved irrelevant however, as Kristatos was knifed to death by Columbo while reaching for a concealed knife. After that, Bond and Melina are back on the Havelock's family boat where Melina says she would like a moonlight swim. Bond drops Melina's robe and she drops Bond's robe, and they go skinny dipping together.
- During filming of For Your Eyes Only it was found out that Carole Bouquet couldn’t dive as she had sinus problems. To create the close-up underwater scenes, slow motion film and fan machines were used. Roger Moore and Boquet both wore diving masks and bubbles were added in by special effects to complete the scenes.
- Melina is the only Bond girl to ever go Skinny - Dipping with Bond.
- Judy Havelock (Literary equivalent)