Arnold is having his 21st birthday party with his friends in Hillwood, there maybe some teenagers from the suburbs that want to crash it very badly. 

SYNOPSIS:

It's a been a very long time since Arnold found his parents in San Lorenzo. And when Arnold was in 6th grade, his parents begin to show Arnold there other friends and a family name The Pickles and Arnold baby sits their kids and it does not go very well and their house ends up exploding from a lot of Ice Cream and Root beer and soda. Flash-Forward to years later, Arnold and his friends are in their 20's and are planning Arnold's 21st birthday, but little does Arnold know, the same babies that Arnold baby sat years ago, now are teenagers they remember Arnold very well and they want to build a giant reptar dinosaur and they even create a giant chocolate green ice cream with achool in it as well. Arnold also begins to fall in love with Helga Pataki but sadly she is dating Wolfgang mainly because to impress her dad. But little does Helga know, Wolfgang does not care about Helga at all and often cheats on her with Helga's sister Olga. Arnold in this wild story, wants to have the best birthday ever but also wants to finally tie the knot on Helga once and for all.

HAPPY BIRTHDAY ARNOLD (1ST STORY IN THE NICKELODEON CINCEMATIC UNIVERISE)