Before Bonanza, David Canary said he did his best work on Gunsmoke
You could say his career exploded after "Nitro."
In 1967, David Canary joined the cast of Bonanza as Candy Canaday, and fans of the show all agreed he was the perfect choice for the Ponderosa foreman. It's a character the actor would forever become associated with, but according to Canary in an interview with the Archive of American Television, the actor did his best work just shy of six months before his debut on the iconic TV Western - on that other iconic TV Western, Gunsmoke.
On Gunsmoke, Canary was cast for a special role in a two-part episode that aired in April 1967. It was called "Nitro," and it was all about a drifter named George who agrees to the dangerous job of extracting nitroglycerin from dynamite, to help a gang of bad guys blow up safes all the better. Although George is homeless and jobless and desperate for a change in his life, he's mostly motivated by love, as he's fallen for a saloon girl whose time he can't afford to consume. Canary said of the episode, "I don’t say this very often, but I’m proud of that piece of work. It was a wonderfully done show."
"Nitro" is a real slow-burner that focuses on Canary's character as he carefully and cautiously works with the explosive materials in long drawn-out scenes that seem to track every bead of sweat that dots the actor's brow and knuckles. It's a tense watch, and Canary's character is an emotional firecracker, whose face contorts into cackles and concern in equal measures. It's no wonder the actor late in his career still looked back at it fondly, "It was maybe some of the best work I’ve ever done. It was a wonderful role."
If you recall the episode, you might at some point have wondered why the episode crawls at such a slow pace. Canary explained this, too. "I was hired for an hour. We shot an hour. And they looked at it and said, ‘We can stretch this into two hours.’" And they did, mostly due to Canary's masterful performance, which fans know ended explosively, before the actor's career would go on to blow up figuratively as he became better known as Candy on Bonanza. Of his brief stint on Gunsmoke, Canary said he enjoyed the camaraderie, saying, "It was great working with James Arness and those people. It was a very good show.”