The show continues to follow a bunch of middle schoolers going through puberty. I found this again to be consistently funny with a great run of jokes (and the occasional song).
There are some interesting new things they try here, including having a several episode arc at summer camp, which has its own specific supporting characters. This season is definitely the darkest, but I mean that in a good way as many of the main characters go through compelling personal struggles.
I'm really enjoying Missy's hormone monstress Mona (voiced by Westworld's Thandie Newton) who was introduced near the end of last season. Newton's casting was surprising as she doesn't have a comedy background, but she kills it as an intense and half-crazed being of passion. Jay (Jason Mantzoukas) and Lola (the show's co-creator Nick Kroll) start dating, which was a great idea since they're both such delightfully weird trainwrecks.
Unfortunately, several of the show's supporting characters felt pushed to the side. Though considering the wide cast, I guess it can't be helped. Also, Missy (voiced by Jenny Slate and and later replaced by Ayo Edebin due to the bad optics of having a black girl voiced by a white actress) doesn't have enough showtime as the rest of the main cast. Although, she does get some good material as she deals with her racial identity.
I found that the show's new character Tito the Anxiety Mosquito (Lydia Bamford) feels a little too reminiscent of the role of the Shame Wizard, not to mention that TIto doesn't have as entertaining a personality.
The show with its focus on burgeoning sexuality continues to push the envelope on what you can get away with on television. Heck, by now it's ripped the envelope into shreds. Every season the show tries to up what it can get away with, and I kind of felt that this was the season that the show has be told "Just because you can doesn't mean you should." Season 4 discusses finger stuff between middle schoolers, and yeah they're animated and voiced by adults, but we didn't need this.
This show isn't for the squeamish or those not fan of really R-rated humor, but otherwise I recommend it as it's one of the funniest comedies out there right now.