Yoav Rotman

Everything is complicated in Yoni's life. He's almost 13, real gifted, but physically undeveloped and struggles daily to grow up before his threatening up-coming Bar Mitzva; He sells homework in order to secretly buy a body building wonder powder, which so far does nothing, he stretches every night with heavy weight tied to his legs and screams with full force in front of the wind to thicken his girlish, unstable voice, that gave him the ridiculous nick name - Helium. (imdb)

An ordinary morning at a small-town High School turns into a nightmare when anonymous figures in masks have committed a massacre leaving four dead students. (imdb)