Steve Landesberg, a comic actor known for playing wry, bookish types and most widely recognized as Barney Miller’s Arthur P. Dietrich, has died of cancer, according to TMZ. He was 65. Landesberg joined the cast of Barney Miller full time in its second season, playing the highly intellectual, unflappably deadpan detective, the breadth of whose impressive knowledge on a wide variety of obscure subjects both amazes and baffles his fellow officers. Dietrich was a mainstay of the show throughout its run, even making an appearance on Fish, the spinoff starring Abe Vigoda (who is still alive).