On the classic sitcom Three’s Company, what was the name of the landlord played by Don Knotts?

Ralph Furley is the answer. Don Knotts played Ralph Furley, often called Mr. Furley, on Three’s Company, the ABC sitcom centered on the Santa Monica apartment shared by Jack Tripper, Janet Wood, and Chrissy Snow. Mr. Furley was the landlord of the apartment building where the main characters lived, placing him directly into the show’s roommate misunderstandings and apartment-comedy setup. Don Knotts joined the series after Norman Fell and Audra Lindley left as the Ropers, making Ralph Furley part of the sitcom’s late-1970s cast change. Three’s Company starred John Ritter, Joyce DeWitt, and Suzanne Somers during its best-known early lineup and became one of classic TV’s most recognizable comedies from the late 1970s and early 1980s.