The principals of YouTube comedy team Smosh, Ian Hecox and Anthony Padilla, are starring in their second movie. And with their sophomore effort, paranormal buddy dramedy “Ghostmates,” the duo say they were more confident going in about their acting abilities – and they started with a story with instead of building a film around their digital personae.

YouTube greenlit and developed “Ghostmates” for its YouTube Red subscription service, and the movie is set to debut Dec. 14 on the $10-per-month service.

“This is a big step and evolution for us. It appeals to a broader audience,” Padilla said. With their first movie, in which the Smosh pals magically travel through YouTube to try to delete an embarrassing video, he said, “it felt like you had to be in the YouTube world to appreciate it.” Netflix last year acquired exclusive streaming rights to “Smosh: The Movie,” produced by AwesomenessTV and Defy Media.

According to Padilla, the “Ghostmates” story has “a lot of heart, and it would work without being a comedy… Our tastes have evolved over the years.”

That said, there’s still a delightfully crude joke at the crux of the plot: Hecox’s character, Eddie, dies in a freak accident after his tie gets stuck in a door – and everyone thinks he expired after an autoerotic asphyxiation mishap. After the socially awkward and unemployed Charlie (Padilla) moves into his apartment, the now-deceased Eddie pesters his new roommate (the only person who can see his ghostly incarnation) until Charlie agrees to help make amends with the living and get to heaven.

“Ghostmates” includes a cameo by rap artist T-Pain, who plays a resident of the ghost world, and co-stars Francesca Galassi and Cristina Spruell.

Hecox said YouTube execs provided only a few notes on the project. “We couldn’t be happier –- they allowed us to make the movie we wanted to make,” he said. “YouTube understands our channel is successful because we do what excites us.” Added Padilla, “With this one, we had almost complete freedom.”

The Smosh guys, who started posting videos on YouTube as teens in suburban Sacramento in 2005, now head a multifaceted brand in conjunction with digital studio Defy Media. Smosh’s seven YouTube channels have more than 41 million subscribers covering sketch comedy, animation and gaming, with a full cast of 13. The Smosh team also has produced popular music projects, mobile apps and even a print magazine and comic book series. This summer, Hecox and Padilla hosted a live variety show broadcast on YouTube.

“Ghostmates” kicked off when YouTube’s original programming team approached Smosh about making either a series or a movie, and “we got to work on an idea that excited us,” Hecox said. “We set out in the first movie to make a comedy, and with this one we set out to make a story first and foremost.” Noted Padilla, “Some scenes are bipolar. They get really serious, then you’re hit with some comedy bits.”

The movie was shot over 15 days this summer in Long Beach and Malibu, and the relatively quick turnaround on the project made it a no-go for some prospective directors Hecox and Padilla approached before they landed Jack Henry Robbins (son of Tim Robbins and Susan Sarandon), whose credits include “Ultimate/Ultimate,” a mockumentary series for Spotify about the EDM scene. “Jack took on the challenge,” Hecox said, adding that Robbins contributed several one-liners.

Meanwhile, the duo considered including a nod to “Ghost,” the 1990 romantic thriller starring Patrick Swayze and Demi Moore, with a joke pottery scene. But they scrapped the idea because “we thought it would be too hokey,” said Padilla, who’s never actually seen “Ghost.”

“Ghostmates” is produced by Defy Media with executive producers Padilla, Hecox, Barry Blumberg and Jeffy Can. The film is produced by Carrie Lynn Certa and Ryan Finnerty, a longtime Smosh writing partner who also scribed the film.

Watch the trailer for “Ghostmates”: