That's the way things happen on the Polar Express!
A Connecticut train conductor pulled double duty when he conducted the Yale Glee Club in a spontaneous rendition of a Christmas song.
"I love music," Bob McDonough, a conductor on the Metro North Railroad told InsideEdition.com. "I sing in the shower, and I'm constantly singing, much to the dismay to my co-workers."
But his amateur talent turned professional when, he happened to be on the same train as the Yale Glee Club over the weekend, and conducted the choir in an impromptu performance of "In the Bleak Midwinter."
And if McDonough looked familiar to the singers, it was because he had done the same thing last year.
He said he was en route to work on a passenger train this past weekend when a colleague mentioned his friends at the Yale Glee Club were on the train too.
"I walked in and they all burst out laughing," McDonough said. "I said 'What are the chances of them all coming?'"
They did a practice run before McDonough led them in the carol, timing the song between stops and announcements.
Last year, McDonough went viral after musically conducting the glee club in "Carol of the Blues."
He told InsideEdition.com the group was taking the train he happened to be working on during their annual winter performance at the Yale Club in New York City, located near the Grand Central Terminal.
"I put them in their own car," he joked. "No matter how great they sound, someone's going to complain. So I shut them up."
He then started chatting with the group, and suggested that since he was the conductor, he should also "conduct" the group in a song.
McDonough explained he was originally inspired by his fellow train conductor, who is also a professional orchestra conductor. "I always call him 'the Conductor Conductor.'"
Although McDonough is not in contact with the Yale Glee Club other than their haphazard meetings on the train, and does not have any music conducting opportunities coming up, he hopes he will one day run into Paul McCartney on the job, and be invited to lead the former Beatle in a song.