Atkin played Morty Melnick in the comedy film
Meatballs (1979), for which performance he earned a
Genie nomination. Atkin had a role in
William Fruet's horror film
Funeral Home (1980), as well as the role of Sam in
The Adventures of Sam & Max: Freelance Police, and also played
Mario's and
Luigi's archenemy
King Koopa on
DiC Entertainment's cartoon version of
Super Mario Bros. (notably, he was the first English voice actor for the character). Playing Koopa in all three Mario animated series, he was one of the only voice actors to appear in all three series as the same character. In 1977 he appeared as Talbot, an inept police officer, in an episode of the British television series
The New Avengers, the first of four episodes to be set and filmed in Canada. He voiced Mr. Mushnik on
Little Shop, loosely based on the movie
Little Shop of Horrors. He also played characters in other series such as
Beetlejuice,
Bad Dog and
Ruby Gloom. Atkin appeared in more than 75 films and on many television series. He did voice-over work in approximately 3,000 television and radio commercials, notably for the
Leon's Furniture chain, for which he won three
Clio Awards. He appeared in 95 episodes of
Cagney & Lacey as Sergeant Ronald Coleman. Atkin played Judge Alan Ridenour in a recurring role on the television drama
Law & Order: Special Victims Unit, a role he also played in
Law & Order: Criminal Intent and
Law & Order, and was the voice-over in
Leon's and "Buy Israel Bonds" commercials in Canada. He also made a cameo playing a bus driver in the classic film
Atlantic City (1980) starring
Burt Lancaster, and was the voice for Morty in the television series
Jacob Two-Two. He made a guest appearance in 2010 as a rabbi on the CBC Television series
18 to Life. ==Personal life==