He wasn't necessarily a household name, but you'll probably never forget the character he played. James B. Sikking took on the role of Lt. Howard Hunter, a no-holds barred SWAT-type on the classic Hill St. Blues. 

If that doesn't ring a bell, his picture almost certainly will if you ever watched the show. Sikking played the pipe-smoking gung-ho officer who was always over-ready for action. He had an extensive career in TV, but it was the role of Hunter for which he'll likely be the most remembered. He also memorably appeared in a very different role, playing the dad on the series Doogie Howser, M.D.

He was 90. 

James B. Sikking, Actor on ‘Hill Street Blues’ and ‘Doogie Howser,’ Dies at 90