Steven R. McQueen is adjusting to life in a new city with a little more success than his “Chicago Fire” character adjusts to being part of Firehouse 51.

The former “The Vampire Diaries” star, who is introduced in the Season 4 premiere at 9 p.m. Oct. 13 on NBC, successfully completed the Bank of America Chicago Marathon on Sunday.

“Was tough but did pretty well,” McQueen tweeted Sunday after finishing the 26.2-mile marathon in 4 hours, 16 minutes and 39 seconds (unofficial on the marathon results page).

McQueen, co-star Kara Kilmer and executive producer Matt Olmstead teased the new season Friday during a call with reporters. (Watch the Season 4 trailer at the top of this story.)

McQueen’s character, Jimmy Borelli, doesn’t have a smooth an entry into Firehouse 51. The new candidate is dumped bound and nearly naked on the firehouse driveway by his brother, who works at another firehouse.

“It was a great way to meet the cast and crew,” McQueen said. “Everyone was there and I met them all in my boxers and wrapped up in toilet paper.

“I don’t think there’s a better way to make an entrance.”

Steven R. McQueen

Jimmy Borrelli (Steven R. McQueen, center) tries to make peace with Chief Boden (Eamonn Walker) as Jimmy’s brother, Danny (Andy Ahrens), listens in “Chicago Fire.” (Elizabeth Morris/NBC)

Chief Boden (Eammon Walker) isn’t impressed by the new candidate, and Jimmy has to make amends with his new boss and members of 51.

Kilmer, who plays paramedic Sylvie Brett, said as the season opens Firehouse 51 is feeling a bit raw after losing Leslie Shay and Peter Mills last season. Borelli’s new co-workers do eventually embrace him, but there is an adjustment period while they test him “in a friendly way” to figure him out.

“If you’re running into a burning building, you need to know that the person who’s running in there with you is going to have your back,” she said. 

McQueen suggested that Borelli’s adjustment period might be more challenging than Kilmer said.

“People are going to—I don’t know if I’m allowed to say this—but bust your balls” when you’re the new candidate, he said, adding “While they’re tough on him, he finds a way to hold his own pretty quick.”

McQueen seems to be holding his own in Chicago and in his new job, which he landed in part with the encouragement of “Chicago P.D.” star Jason Beghe. Beghe approached Olmstead about hiring McQueen. (According to McQueen the two actors used to work out together in Malibu.)

“Jason talked up Steven not only as a talent but as a person,” Olmstead said. “Which goes a long way because you go to Chicago [and] you’re away from home. You kind of have a new family. You’re going through the cold. It takes a certain personality and you kind of have to go through it together.”

McQueen said he jumped at the chance to come to Chicago “to play an American hero” and is excited for the possible opportunity to do a “Chicago Med” crossover to work with Oliver Platt.

He’s also enjoying his new work home. (I’ll ask him again during a winter cold snap.)

Despite getting to see a lot of the city while filming on location for the “Fire” action sequences, he wanted to take in the whole city, he said Friday, by running the marathon.

When I suggested that he might not make it to work Monday after his 26.2-mile running tour of the city, he, Kilmer and Olmstead laughed.

“Oh, yes I will! I won’t let it interfere with work,” he said. “I already promised that.”

NBC has confirmed that yes, McQueen reported for firehouse duty Monday.