"Constantine" TV series cast Matt Ryan seems to be channelling the spirit of Welsh comedian Rhod Gilbert in the way his character talks, according to a film critic. Meanwhile, the Welsh actor confessed that he was anxious a few weeks prior to series being picked up by NBC.

Cardiff film critic Gary Slaymaker said that more than the serious Keanu Reeves version in the 2005 "Constantine" movie, Matt Ryan's has "the same sing-song delivery as Rhod, and there's clearly a lot of cheek in his performance."

The critic said that "Constantine" TV series cast also opted to assume a "world-weary attitude" of his character, which is more in keeping with the Hellblazer comics than what Keanu Reeves did.

"Matt looks really great in the role - far more in line with how John Constantine should look than Keanu was with his black hair and Californian surfer dude voice," he wrote.

Meanwhile, "Constantine" TV series cast Matt Ryan told TV Fanatic that he was nervous for a bit before the show was picked up by NBC.

"Just this whole waiting period after you finish (filming). In the first couple of weeks you're fine, you take a bit of a holiday, do your thing and then we were really waiting ... We were really pleased that it's been picked up and we think it will be great."

He said he tried to downplay the whole thing in order to protect himself if the show was not going to be picked up.

"I was not building up the expectations, like okay, alright, we'll move forward, what's going to be next and all these things, so it was a surprise (when the series was picked up), which was great," he said.

Based on the Hellblazer comics, John Constantine is a demonologist and master of the occult who makes it his life's work to send wayward demons back to hell. It will premiere on NBC in the fall.