Ellery Queen (1975)

Season 1: Episode 5

News mogul Henry Manners is murdered in an express elevator to the 12th floor of his building with nobody inside the elevator except the victim. The suspects include Manners' sister who had previously run the paper while her brother was absent in WW II, the right-wing columnist who was always getting the paper into legal hot water, the Editor being forced into retirement, and (yes, you knew this was coming) the paper's lawyer. Ole Frank Flannigan is on the scene too making the usual nuisance of himself and trying to beat Ellery to the solution. They'll have to take things one day at a time in this case.