Not every actor who works on a show is pals with the rest of the cast. In fact, some shows wind up with lead characters who practically hate each other. In other cases, hush-hush relationships and high-profile breakups make it impossible for cast members to stand each other.

But in the case of Nick Kroll and John Mulaney, fans wonder how close they are behind the scenes of 'Big Mouth.' The show is a pretty dynamic project, and the Netflix series seems to have a bright future ahead of it.

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While Nick Kroll is listed as a co-creator of 'Big Mouth,' along with Andrew Goldberg, Mark Levin, and Jennifer Flackett, it's not his first time voicing characters alongside John Mulaney.

Nick, who's worth an impressive $18 million, has been working with his pal John for more than a decade. Andrew Goldberg is also a childhood friend of Nick's, while John came on the scene a bit later.

Unlike Nick, John didn't grow up in a billion-dollar family, but he's earned a pretty good living as a comedian, too. Part of his wealth came from a partnership with Nick; the two collaborated on Broadway with 'Oh Hello,' which was a serious hit and was later released on Netflix, explained CheatSheet.

Nick explained that he and John had worked in comedy together since at least 2005, but that the pair of them had known each other since college. At the time they were working on 'Oh, Hello,' Nick elaborated in an interview that it felt like the Broadway show was the height of his career.

He said that in addition to the show being both a critical and financial success, he was working with his best friend, and John's wife was also doing their makeup before each show. He was afraid the run — and the high that went along with it — would end, noted Kroll.

Of course, he needn't have worried. Fast forward a few years, and Nick and John were together again, developing a hit show where they could both dive into everything they've always wanted to joke about. And Netflix was more than willing to give them a platform to do it.

Fans of the pair aren't surprised to learn they're pals beyond the show, though. It's evident from watching their other work together that Kroll and Mulaney work well together, and there's no bad blood between them.

Nick also spoke out in support of his friend after John's rehab announcement, further cementing proof of their friendship off-screen. The two also indulge in interviews where they've explained that all of their middle-school experiences are channeled into 'Big Mouth,' confirms NPR, so clearly, they're close and totally not awkward with one another.

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