Shaft's Big Score! (1972)

Queens private detective John Shaft is contacted by his old friend Cal Asby, an insurance salesman and mortician, who tells him he’s in trouble and asks him to come immediately. As soon as Shaft arrives, Asby is killed by a bomb planted inside of his house. Shaft is questioned by a suspicious police Captain Bollin, but is quickly released due to a lack of evidence. Asby’s business partner Johnny Kelly owes mob boss Gus Mascola $250,000 in past gambling debts, money he had planned to take from his partner but had been moved and hidden before his death. Asby’s house is ransacked before Shaft, Kelly, and Asby’s sister Arna can investigate. When the perpetrator runs out, Kelly blocks Shaft from chasing him while pretending to help. Suspicious, Shaft tells Arna that he wants to inspect Asby and Kelly’s partnership papers, warning Kelly he intends to protect Arna.

Bollin reveals to Shaft that Asby and Kelly were running a numbers racket with the insurance company and funeral parlor as profitable fronts but because they agreed to keep the scam clean, he looked the other way. Now that Asby is dead, however, Bollin fears that the mob will move in to take over their businesses. Although Bollin suspects that Shaft may be involved with one of the gangsters, he asks him to help, and Shaft coolly agrees. Shaft forces one of Kelly’s numbers runners to reveal the location of the operation’s headquarters. Upon arriving, he is seduced by Kelly’s mistress Rita as revenge for her lover’s mistreatment. While the two have sex, Kelly is threatened by Mascola, who demands not only to be paid but to be made an equal partner in the operation. Kelly is reluctant, telling the mobster that he is worried about Shaft’s interference on Arna’s behalf, but after Mascola promises to “take care” of Shaft, Kelly agrees to a 50-50 partnership.