Justin and Hailey Bieber Pack on the PDA at Justin Bieber: Seasons Premiere

Justin and James hilariously struggle to keep up with the wild and unpredictable moves of their strict toddler instructors.

Justin Bieber continued his one week "residency" on "The Late Late Show" by getting up to even more shenanigans with James Corden after playfully bickering their way through an entire Carpool Karaoke segment.

This time, they took on LA's most challenging hip-hop dance classes, taught entirely by toddlers, and then hit the open road to raise money by running their own food truck.

Behind the wheel again, this time no one was picking a fight with anyone. In fact, from the jump Justin was there with words of support as James pulled out.

"You're doing great so far, I'm really proud of you," he said.

"We've traveled ten feet, but I appreciate it," James replied.

From there, all they needed was a menu and a theme song -- because every food truck needs a theme song, right? Justin quickly came up with a simple hook based on the phrase "food dudes."

And James came up with the perfect menu item. "You're Canadian and I'm British. You know the best food we could do?" he asked, before answering it himself. "Tacos!"

And so, the Despetaco was born, and it even had its own theme song. Justin expanded the menu by offering up a grilled cheese sandwich and they were on their way, with all proceeds going to the LA Food Bank. Even better, they only asked that their customers pay what they thought they deserved.

For some customers, though, just seeing Justin Bieber was enough. His "number one fan" was stunned upon seeing him and willing to risk a dish even though she said she was deathly allergic to fish. He promised the grilled cheese was cooked on a different grill, but upon delivering it, James still suggested to her, "Don't eat it."

The whole thing was a huge success, perhaps bigger than either guy thought. And as they realized they were overwhelmed and in over their heads, it was still better than what they had to endure in the studio.

It was quite possibly the most adorable thing we've ever seen, as these kids were really working it up front as James and Justin tried desperately (despataco?) to keep up with their ad-libbed moves. One of the kids had truly killer moves, while one young lady was more about running back and forth and that toddler staple, jumping up and down.

We loved Justin's commitment to following them up, down and all around and even through cartwheels if necessary. James had to draw the line there.

Check out their adorable, and genuinely challenging dance moves in the video below:

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