People who have read “The Strain” books have been waiting a season-and-a-half for one of the novels best characters to turn up on the show. Their wish was granted at the end of episode 6 with the debut of Mr. Quinlan, the strigoi who wants to stop the Master.

Coming into Season 2, many fans believed Vaun (Stephen McHattie) was Mr. Quinlan until his name was revealed. Showrunner Carlton Cuse told IGN Aug. 8, they felt it would be fun to mislead book readers while also building up Mr. Quinlan.

“It also makes it feel like Quinlan would be more formidable if we introduced a guy who seems pretty bad a-- and then discover that Quinlan is even more bada--,” Cuse dished.

Rupert Penry-Jones, who is portraying Mr. Quinlan on the show, told the Hollywood Reporter Friday he’s glad to have the role, but admits he’s nervous fans aren’t going to like him. Vaun was not only a fan-favorite, but also his personal favorite character on the show.

“So I was basically taking over from someone I thought was fantastic. To step into his shoes is what the pressure is. As a fan, I’m sort of upset that he’s no longer in the show. I’m nervous about people thinking that he should have stayed as Quinlan. But Guillermo made me feel nothing but confident and comfortable about it,” he said.

Penry-Jones also added his version of Quinlan is different from the one you’d find in the books. His is more human, as the one in the books had no ears, no nose and only spoke to people by telepathy. As episode 6 showed, this Quinlan has the ability to speak physically.

In an interview with TV Fanatic in August 2014, Guillermo Del Toro revealed Mr. Quinlan is one of his favorite characters, along with Angel (Joaquín Cosio) and Setrakian (David Bradley). “Those are the characters I get my rocks off the most because they’re great, unlikely heroes," he explained.

Fans can expect to learn more about Mr. Quinlan in “The Strain” Season 2, episode 7. In episode 6, Quinlan told the elders he was there to stop the Masters and he was looking for day hunters, which will likely once again be Setrakian and Gus (Miguel Gomez).

“The Strain” airs on FX Sunday nights at 10 p.m. EDT.