Tony Rosato, one of only three comedians to perform on TV as a cast member of both SCTV and Saturday Night Live, has died of an apparent heart attack. Rosato was 62.

Born in Naples, Italy, on Dec. 26, 1954, Rosato immigrated to Canada with his parents when he was 4. He could have become a chiropractor but dropped out of the University of Toronto instead to pursue improvisational comedy at The Second City. That decision worked out well for him. Rosato joined the cast of SCTV for its third season, and first on the CBC in 1980 — he, Robin Duke and Rick Moranis were hired there to replace John Candy, Catherine O’Hara and Harold Ramis.

Rosato’s most prominent original character on SCTV, a drunk chef with a TV show named “Cooking with Marcello.”

Rosato and Duke then both got the call again as subs for an even bigger, even more prominent sketch comedy show in SNL during its sixth season. That lasted only one episode before the Writers Guild went on strike. He’d return for a full season (SNL Season 7) in 1981-1982, where his impersonations included original SNL star John Belushi, plus Ed Asner, Ed Meese, Richard Nixon, Rip Taylor, and Lou Costello.

Here’s Rosato as Costello in a bit for Weekend Update that season.

Rosato also often appeared in sketches with Chicago Second City alum Tim Kazurinsky, who offered a tribute Wednesday on Twitter.

SNL would undergo many changes in the mid-1980s (with Martin Short becoming the third SCTV alum to join SNL), and Rosato went back to Canada, where he found more success on TV on shows such as cop drama Night Heat, and lots of voiceover work throughout the 1990s in animated series, most notably as Luigi in The Adventures of Super Mario Bros. 3 and Super Mario World.

A gap followed in the first decade of this century, during which he served two years in maximum-security prison and another two years institutionalized after a charge of criminal harassing his wife eventually led to a diagnosis of Capgras delusion. It’s a mental illness in which the person mistakenly believes his/her family or loved ones have been replaced by impostors. He was eventually released from the hospital in 2009, and from probation in 2010.

Whereupon Rosato went back to his roots, taking classes once more at The Second City, and small roles on TV.