The coolest kids at school, "The Top Ten", are disappearing one-by-one. What could it be? Aliens? Wookalars? Zombie hummingbirds pecked out their eyes and now they can't find their way to school? Maybe they're just falling asleep due to the boring script? Nope, it's some butthole killing them because of some dumb reason. Honestly, it doesn't matter, because by the time you get to the end you'll be 99 and 44/100% asleep. Not because it's a horrible movie, just a long-winded one that has zero idea what a slasher movie audience wants. A slasher audience wants insane violence, hot nudity, blood, gore, a fun story and a badass killer. HBTM has none of those things. There's very little violence, the killer is weak, zero nudity, only a handful of blood, weak gore and the story is overly complicated.
Not a bad watch, but nothing to get excited about either. As far as early 80's slashers go, HAPPY BIRTHDAY TO ME is watchable and fun to laugh at, but average.
He bet somebody $20 he could make that jump. Totally worth it.