Given the task definition and input, reply with output. 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.

Fact1: operative Paul Shepherdson is summoned by CIA director Tom Highland to look into murder, Fact2: Gere is introduced to young FBI agent, Fact3: young FBI agent is expert on former Soviet operative known as Cassius, Fact4: interrupted by Ben 's wife is unable to Geary in front of family, Fact5: Paul warns Ben to pull out due to possibility of harm to himself but family
Two FBI agents are conducting surveillance at a warehouse. As a U.S. senator Dennis Darden Ed Kelly walks out of the door, he is approached by an assassin from behind who slits his throat and escapes. The agents rush to the scene to find the man dead. However, they could not identify the assassin as he committed the murder in darkness. Later, CIA officers arrive on the scene and take charge. Retired operative Paul Shepherdson Richard Gere is summoned by CIA director Tom Highland Martin Sheen to look into the murder. He is introduced to a young FBI agent, Ben Geary Topher Grace who is an expert on a former Soviet operative known as Cassius. Geary reasons that Cassius is the assassin due to his signature throatslitting garrotting method. Paul and Ben visit Brutus Stephen Moyer, one of Cassiuss proteges, who is locked up in prison, to learn the whereabouts of Cassius. They provide him with a radio and leave. The prisoner then swallows the batteries from the radio and fakes a poisoningupset stomach. Upon arriving at a hospital, he regurgitates and spits out the batteries, overpowers the medical staff, and escapes. In the basements garage, he is attacked by Paul, who reveals himself to be Cassius himself, the very operative who had previously trained the fugitive. Cassius slits his throat. He then moves to eliminate Ben too, only stopping when interrupted by Bens wifeCassius is unable to murder Geary in front of his family. Upon investigating the crime scene, Ben grows increasingly suspicious of Paul. Meanwhile, a Russian terrorist and murderer, Bozlovski Tamer Hassan, has entered the U.S. As the investigation deepens, Paul warns Ben to pull out, due to the possibility of harm not only to himself but his family. Ben, who has become obsessed with the idea that Paul is Cassius, starts his own parallel investigation. Meanwhile, Paul tries to contact Bozlovski in a factory where he escapes after an intense firefight. Ben examines another throatslitting murder of Bozlovskis associate at the same site and is now convinced Paul is indeed Cassius. Ben pieces together the events of Pauls life and determines that not only is Paul actually Cassius, but also that he is systematically murdering the people involved in the death of his wife and child, who were assassinated by Bozlovski. Paul has now tracked down Bozlovski to a shipyard warehouse. A while later, Ben also arrives at the building. After being confronted with the evidence, Paul confesses everything. Paul then confronts Ben with the fact that Ben is a Russian spy, which Paul learned at one of Bens informant dropoffs. He is able to convince Ben that Bozlovski is the actual threat. When Ben reveals that he has plans to return to Russia after this is over, Paul tries to convince him to stay in the FBI and with the family he has grown to love. Together they hunt down Bozlovski inside the shipyards warehouse. Bozlovski attacks Paul and Ben, and in the ensuing struggle, a mortally wounded Paul slits Bozlovskis throat using his garrotewatch. However, Paul himself later succumbs to his own injuries. As the only witness, FBI agent Ben relays the incident to his superiors and claims that Bozlovski was Cassius, thereby securing Pauls reputation and recognizing his heroism. As Ben departs, the CIA director Highland asks him whether he would ever consider working at the CIA. The film ends with Ben returning to his home as a nowdefected man who is no longer a double agent.