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Movies like Hart to Hart: Old Friends Never Die (1994)

The Harts find themselves in the middle of a dangerous murder plot, but it isn't clear if the plot it a famous author's fictional murder-mystery, or an actual murder plot, until Jonathan finds himself the unsuspecting target of a killer. It begins to look like the culprit behind the plot is an old friend, Frank Crane, but there may be a connection to a corporate takeover of Hart Industries as well.