The Director of a large anonymous corporation (uncredited Duvall) asks surveillance expert Harry Caul (improbably pacamac-ed hero, Hackman) to record a young couple's private conversation. The film opens with Caul and assistants (including John Cazale) endeavouring to capture the said exchange in a busy square with an assortment of concealed mics.
Haunted by the bloody consequences of an earlier assignment, Caul becomes convinced that his ingenious invasions of privacy will put the young couple's lives at risk. The tapes contain the phrase "He'd kill us if he had the chance", and it is this which Harry obsesses over. Finally, in taking action to prevent further bloodshed, he shatters his own deeply private world.
Shot between two "Godfathers", it is the work of a film maker at the height of his creativity. In contrast to the breadth of Coppola's mob sagas, "The Conversation" is an intricate and unsettlingly subtle character study, with a very strong performance from Hackman.
In latter-day films it's hard to find protagonists as ambiguous as Harry Caul, but the questions raised about the ethics of surveillance are as relevant as ever. Hackman's character in "Enemy of the State" had shades of Caul, down to his cage-like workspace and total paranoia.
Like Hitchcock's "Rear Window" it is also a study of cinematic voyeurism, differing in its concern with eavesdropping rather than watching, and with the added edge that the voyeur is implicated in the killings.