In this dialogue-driven, "second coming of age" comedic drama, Felix has all but given up on his pursuit of becoming a filmmaker when he meets Stella, a down to Earth, chain-smoking cinephile, whose unexpected friendship inspires him to start writing again–and falling for her. Never hesitating to take steps outside of reality through the use of movies within movies, found footage and action sequences, Mountainside is also a love letter to film itself.

When two lazy sisters argue about whose turn it is to replenish the snacks, they are transported to a fantastical boxing ring to duke it out.