Animated comedy that was essentially 'Being Human', just years ahead of its time.
Three teenaged guys would be normal most of the time, but could transform into a vampire, a werewolf and a...erm... Frankenstein's Monster (no idea how that worked!) by giving a high-five, and would then go and solve supernatural crimes together.
All teenage supernatural crime fighters need a wise elder counsel of course, and this lot had none other than Count Dracula, who they referred to as "Big D" - probably causing Bram Stoker, if not Vlad the Impaler, to rotate in his grave.
This was a Hanna Barbera show of half an hour apiece, and, as far as I can recall, it ran on a Monday afternoon/evening in the UK.