Ed Helms is about to step into Clark Griswold’s shoes as part of a new “Vacation” reboot. Before then, he’s showing a new side to his persona — bluegrass crooner.

Helms just dropped an album on an unsuspecting public, the eponymous release “The Lonesome Trio.” The “Hangover” star doesn’t just sing in his band. He also plays the banjo, guitar, piano, harmonica and trumpet.

 

The album is getting serious notices in the music media, meaning he hasn’t embarrassed himself by straying far from his entertainment roots. Still, the notion of the guy who loses a tooth but gains a face tattoo in the “Hangover” series playing bluegrass is a head scratcher. It’s not the first time an unconventional singer sang for his or her supper. Consider the following five crooners who more or less took the culture by surprise.

William Shatner
The “Star Trek” icon went from a joke to a seriously funny thespian who excelled in self-awareness. His musical career charted a similar course. “Star Trek” fans chortled over his rock covers like “Tambourine Man” and “Lucy in the Sky with Diamonds.” Years later, Shatner gained some industry respect when he teamed up with veteran songsmith Ben Folds for the musical project “Has Been.”

Jeff Bridges
We all know the Dude Abides … but who knew he sings as well? Bridges released “Be Here Soon” in 2000 to little attention. His star rose significantly following his Oscar-winning turn as a crusty country singer in “Crazy Heart.” Naturally, he followed that up with his self-titled 2011 release.

Robert Davi
The tough guy from “Die Hard” and “The Goonies” can sing? The versatile actor not only sings, he can crush the Sinatra songbook like few of his peers. Like Bridges, Davi started his career in music and later segued to the silver screen.

Russell Crowe
The Aussie actor is a true chameleon, the type who somehow looks different in every role. We were still taken aback when he opened his mouth to sing in the recent screen adaptation of “Les Miserables.” It’s a reminder of his other gig, one perennially overshadowed by his sterling work on the big screen. He’s the lead singer of the Australian rock band 30 Odd Foot of Grunts.

Kevin Bacon
We learned Bacon could dance from the 1984 drama “Footloose,” a pivotal moment in the actor’s young career. A decade later he embraced a new side gig as one half of the Bacon Brothers. The actor and sibling of Michael Bacon don’t take themselves too seriously on stage, but their devotion to American music is palpable. And, best of all, it’s no joke.