Definition: In this task, five ordered key facts are given. All the given facts are expressed in natural language. Your job is to generate a story 100 to 1000 words long, that includes all the facts given as input in their order of appearance while expanding upon them to produce a broader, yet coherent, narrative.
Input: Fact1: plane crash victim is carrying false letters about forthcoming Allied invasion of Greece rather than obvious target of Sicily, Fact2: Montagu On advice of procures body of man medical expert, Fact3: he and assistant after take corpse to waiting submarine proper preparations, Fact4: body is processed by local authorities observed by German and British consulate staff, Fact5: attache case containing letters is returned to London as part of personal possessions of Martin

In 1943, Royal Navy Lieutenant Commander, Ewen Montagu Clifton Webb, comes up with a scheme to deceive the Nazis about the impending invasion of Southern Europe. It entails releasing a dead body just off the coast of Spain, where strong currents will almost certainly cause it to drift ashore in an area where a skilled German secret agent operates. The corpse will appear as a plane crash victim, the nonexistent Royal Marine, Major William Martin, who is carrying false letters about a forthcoming Allied invasion of Greece, rather than the obvious target of Sicily. Time is short, but the impatient Montagu is finally given approval to carry out the mission: Operation Mincemeat. On the advice of a medical expert, Montagu procures the body of a man who died of pneumonia so that he will seem to have drowned from the grieving father. Then, after proper preparations, he and his assistant, Lt. Acres Robert Flemyng, take the corpse concealed in a canister packed with dry ice to a waiting submarine. The submarine travels to the Mediterranean, along the way evading a depthcharge attack, before surfacing at night to release the body. As hoped, the body washes ashore on a Spanish beach and is processed by local authorities, observed by German and British consulate staff. After the attache case containing the letters is returned to London, as part of the personal possessions of the deceased Major Martin, Montagu is disappointed the documents dont appear to have been tampered with. However, a laboratory expert confirms that the key letter, describing the false Allied attack in Greece, was cleverly opened and resealed. Hitler is convinced the document is genuine, even though a German intelligence officer is sceptical. He orders an IRA Nazi spy, Patrick OReilly Stephen Boyd dispatched to London to investigate. What OReilly uncovers is inconclusive, in his mind, until he checks out Martins fiancee, Lucy Sherwood Gloria Grahame. She is the roommate of Montagus assistant, Pam Josephine Griffin. OReilly shows up at their flat, posing as Martins old friend, on the same day Lucy received news that her real boyfriend has been killed in action. Her genuine grief mostly convinces OReilly. As a final test, however, he leaves the address of his lodgings in north London, telling Lucy to contact him if she needs anything. He then informs his German superiors by radio to expect a message from him in an hour, unless British counterintelligence comes for him. Montagu almost makes this very mistake, but realises in time why OReilly left his address and, with some difficulty, convinces his superiors not to order OReilly to be arrested. OReilly then sends a Martin genuine! radio message, and the Nazis transfer most of their Sicilybased forces to Greece, making the Allied deceit successful. After the war, Montagu leaves a medal he was awarded at the grave of the man who never was.