Professor Frank N. Stein, frequently referred to simply as Prof, is one of the main characters in the series Decap Attack. He is a stereotypical mad scientist, with green hair and a thick German accent, both of which are fake - he's actually a blond former choir boy from Cardiff. He lives in Castle Frank N. Stein in Transylvania, with his sadistic assistant Igor and the monsters Chuck and Head. He supports Transylvania United (the Garlics).
Prof is from Cardiff. When he was young, he was looked after by a Nanny and his favourite books were the Mr Cuddle Bunny series. He was a member of the Mid-Glamorgan Boys Choir. In prep school, he was bullied by three prefects called Stinky Bates, Pongo and Basher, who copied his homework, hit him with twangy rulers and stole his conkers. The young Prof got his revenge, painting the prefects' heads green. Exhilarated, he decided to go to university and study biology so that he could become a mad professor and "make his own friends". Some time after this he began dying his hair green and effecting a German accent.
After this, Prof met Igor who moved into Castle Frank N. Stein and began to work for the Welshman. After an unspecified length of time, Frank would go on to create Chuck D. Head, his first successful man-made monster. He would later go on to produce Boris and Daphne, two monsters who quickly left the castle. He also performed a brain transplant on Detective Case (replacing his brain with a grapefruit) and had his mother assist him on another corpse.
Frank has appeared in almost every Decap Attack story, so his chronology can be seen in the list of Decap Attack stories. However, there are a few exceptions:
- Issue 102 - Life With the Snagsbys (although he is mentioned over the telephone)
- Issue 114 and Issue 115 - Chuck and the Cheese Factory
- Issue 123 - Love is Blind