Blake Shelton took girlfriend Gwen Stefani and her three sons as his dates to his UglyDolls movie premiere in Los Angeles on Saturday (April 27), and he admits it made him seem a lot cooler in the boys' eyes.

"My cool points went up with this one," Shelton joked to Extra on the red carpet. "The kids are super excited about this movie. I’m excited for them, because it’s such a great message."

Stefani has three with ex-husband Gavin Rossdale: 12-year-old Kingston, 10-year-old Zuma and 5-year-old Apollo. In three-plus years of dating Shelton, they've rarely — if ever — stepped out as a fivesome in an official capacity.

“It’s a rare thing for Gwen and [me] to even get out at all," Shelton explains. "We don’t really get a chance to do anything. One of the two of us are working or the kids are in school — it just never works out for us to all go out. We get to do it about four or five times a year — this is one of them.”

In the UglyDolls movie, Shelton plays the one-eyed Mayor of Uglyville, Ox. His character has a huge secret he has kept hidden, and it winds up being revealed in the film. “He’s super ugly for one thing," he says of his character, speaking of how he relates to him. "He has a big belly hangin’ off him."

Not only is the country star one of the leads, but he also recorded a song for the movie's soundtrack, "Wallflower and Weeds." UglyDolls also stars fellow Voice judge Kelly Clarkson portraying, the leader of the group who is searching for something more. Clarkson also sings "Today's the Day," "Broken & Beautiful" and "Couldn't Be Better" on the soundtrack.

UglyDolls hits theaters on May 3.

See Pics of Blake Shelton, Gwen Stefani and Her Boys at UglyDolls Premiere: