Lord Peter Wimsey Mysteries: Murder Must Advertise (1974)

Just before copywriter Victor Dean fell to his death, he wrote to his supervisors at Pym's Publicity Ltd., hinting at improprieties within the agency. Concerned, the company's top brass hires Lord Peter Wimsey (Ian Carmichael) to work undercover and investigate. Was Victor's death an accident or murder? Also starring Peter Bowles and Bridget Armstrong, this BBC miniseries is based on the novel by Dorothy L. Sayers.