TORONTO — Don McKellar says it's ironic that he plays the lead voice on the animated series Odd Job Jack.

The show, which chronicles the adventures of its perpetually unemployed title character, is actually McKellar's longest-running gig yet.

"It in itself is a fantastic job for me," he says on the phone after a recent studio session in Toronto. "But it's funny that this show about temporary jobs is the longest job I've ever had. There's some irony there."

McKellar's list of "odd jobs" includes acting, writing and directing credits spanning more than 15 years, a Genie for best supporting actor in the 1994 film Exotica and, last month, a Tony for best book of a musical for The Drowsy Chaperone.

The resume is a far cry from that of Jack Ryder, a 25-year-old underemployed sociology grad with a hefty debt whose resume boasts positions as a mortician, hamster wrangler, meter maid and crab fisherman.

The show - produced by Smiley Guy Studios in Toronto and airing on The Comedy Network - features Jack taking on jobs assigned by an agency which specializes in filling difficult and unusual positions. Outrageous events ensue.

The show isn't afraid to push the boundaries of humour. Smiley Guy executive producer Jonas Diamond says it falls somewhere between The Simpsons and The Family Guy.

The first episode of Season 4, airing Saturday on The Comedy Network (check local listings) features Jack working as a croupier alongside a character voiced by Seinfeld star Jason Alexander.

McKellar, 42, says his favourite episode this year is one featuring Molly Parker (Deadwood), who co-starred with McKellar in the CBC comedy Twitch City.

In that episode, Jack and Parker's character, Alberta, discover an ancient female civilization, featuring an ominous fountain of life. It ultimately turns out it's not filled with breast milk, as Alberta initially assumes.

McKellar says he was surprised when he read that script.

"It's probably the most extreme in terms of images," he says. "They pushed the limits there.

"I read that and said 'you can't be serious about that', but they went for it."

Parker, 34, says doing the voice work for the show was liberating.

"I'd never played a voiced character before and I didn't know really anything about the show other than Don McKellar was involved," she says on the phone from Los Angeles. "I was maybe slightly nervous at first because... I'm not used to depending just on my voice.

"I ended up having such a great time," she says. "It was kind of liberating to be able to go really far and be quite broad and silly and big in a way that I really never let myself do as an actor."

Odd Job Jack will also work alongside characters voiced by John Goodman (Roseanne), Jerry Stiller (Seinfeld), Sean Cullen (The Sean Cullen Show) and others during the 13-episode season.

When the show was initially conceived in the late 1990s, Smiley Guy intended it to be aired completely online and interactive, so viewers could play the main character's job or read characters thoughts as the show progressed.

The Comedy Network offered to air the show on TV with an interactive website. Oddjobjack.com features a new game to match each episode as well as video recaps.

Executive producer Jonas Diamond says he'd like to some day air Odd Job Jack live on the Net.

"I do think it's coming full circle again where now the technology is catching up with the original thrust of the idea," he says.

The show is also shown in Italy, Spain, South Africa, Portugal and across Latin America.

Odd Job Jack returns for its fourth season Saturday July 22, at 9:30 p.m. on The Comedy Network.