Which executive loses a foot in the John Deere lawnmower accident on Mad Men?

The executive who loses a foot in the John Deere lawnmower accident on Mad Men is Guy MacKendrick.

MacKendrick is a confident accounts executive from the London-based agency Putnam, Powell, and Lowe. He is sent to Sterling Cooper during season three’s “Guy Walks Into an Advertising Agency,” as his firm prepares to take over the agency. His arrival initially represents a major professional threat to the existing leadership.

During a chaotic office party, secretary Lois Sadler drives a John Deere riding mower over MacKendrick’s foot. Joan Holloway quickly applies a tourniquet, but MacKendrick ultimately loses the foot. The injury is not merely a shocking workplace accident: PPL’s partners decide that his disfigurement makes him unsuitable to lead the takeover, and his career effectively ends.

A common mix-up is confusing MacKendrick with the Sterling Cooper employees present during the accident, including Smitty Smith or Lane Pryce. The scene’s lasting consequence is that the takeover fails, giving Don Draper and his colleagues an opening to create Sterling Cooper Draper Pryce.