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: surveillance expert runs own company in San Francisco, Fact2: Caul is obsessed with own privacy, Fact3: challenging task of recording conversation is accomplished by multiple surveillance operatives located in different positions around square, Fact4: tape of conversation is stolen from him in moment, Fact5: client 's assistant tells him not to look further into matter
Harry Caul is a surveillance expert who runs his own company in San Francisco. Caul is obsessed with his own privacy; his apartment is almost bare behind its triplelocked door and burglar alarm, he uses pay phones to make calls, claims to have no home telephone and his office is enclosed in wire mesh in a corner of a much larger warehouse. He has no friends, his girlfriend Amy knows nothing about him, and his one hobby is playing along to jazz records on a tenor saxophone in the privacy of his apartment. Caul insists that he is not responsible for the actual content of the conversations he records or the use to which his clients put his surveillance activities. However, he is racked by guilt over a past wiretap job which resulted in the murder of three people. This sense of guilt is amplified by his devout Catholicism. Caul, his colleague Stan and some freelance associates have taken on the task of bugging the conversation of a couple as they walk through crowded Union Square in San Francisco, surrounded by a cacophony of background noise. Amid the smalltalk, the couple discuss fears that they are being watched, and mention a discreet meeting at a hotel room in a few days. The challenging task of recording this conversation is accomplished by multiple surveillance operatives located in different positions around the square. After Caul has merged and filtered the different tapes, the final result is a sound recording in which the words themselves are crystal clear, but their meaning remains ambiguous. Caul feels increasingly uneasy about what may happen to the couple once the client hears the tape. He plays the tape again and again, gradually refining its accuracy. He concentrates on one key phrase hidden under the sound of a street musician: Hed kill us if he got the chance. Caul constantly reinterprets the speakers subtle emphasis on particular words in this phrase, trying to figure out their meaning in the light of what he suspects and subsequently discovers. Caul avoids handing in the tape to the aide of the man who commissioned the surveillance. Afterward, he finds himself under increasing pressure from the clients aide and is himself followed, tricked, and bugged. The tape of the conversation is eventually stolen from him in a moment when his guard is down. Caul eventually discovers the truth: the couple were talking about killing the womans husband Cauls client. Caul gets a phone call from his clients assistant, who tells him not to look any further into the matter, and says, Well be listening. Caul goes on a frantic search for a listening device, tearing up his apartment to no avail. He sits amid the wreckage, playing the only thing in his apartment left intact: his saxophone.