He made his Broadway debut in 1857 in "Middle of the Night" and made his first major film appearance in 1959, as Leonard, right-hand man of a criminal mastermind, in Alfred Hitchcock's North by Northwest.
He started doing it, acting, in his early twenties after ending a five-year stint he began at age 17 as a New York Daily News cartoonist. The quirky cast in Burton's homage to fabled bad-movie director Wood included Johnny Depp, Bill Murray, Sarah Jessica Parker and wrestler George "The Animal" Steele.
"Oh, "Tucker" resurrected me", Landau told the London Guardian. The two actors were nearly castmates on Star Trek, but Landau famously turned down the role of Mr. Spock, insisting he couldn't bear the thought of playing such an unemotional character. "Obviously, if you can do that part I saw you do in the theater, you can do this little trinket". "There was a lot of pain, a lot of angst", he told The New Yorker in 1995.
There are some roles that Landau took on in various mediums that could genuinely surprise you - for example, that he voiced the villain Scorpion in the classic 1960's Spider-Man cartoon.
He also gained some measure of fame among Star Trek fans for a role he didn't play, pointy-eared starship Enterprise science officer, Mr. Spock. "I think he thought I was going to be an usher".
He would go on to star in another enormously popular, franchise-spawning television series, Mission: Impossible, for three years.
Landau loved acting more than anything, and felt he had learned so much about it that he wanted to give something back, so he became a teacher himself.
Landau most recently appeared in the 2015 TV film adaptation of the HBO series "Entourage".
Landau is survived by daughters Susan Landau Finch (a casting director and producer whose upcoming projects include Nate and Al, with her father tapped to play Al) and Juliet Landau (a ballerina and actress best known for playing Drusilla on Buffy the Vampire Slayer and its spin-off Angel).