Lord Voldemort 'i am so bad even my toes are bad'

[Sephiroth]

According to the books he already looked like a snake even before he "died". When he returned to Dumbledore he already had red eyes and his inhuman skull and snake-face but not as much as he had in the end. That he was already doomed as a child has been shown in Harry Potter 6. Dumbledore just didn't know that he would become that evil and tried to teach him normally. Still, as he said, if he would have known he would have tried better. Or he probably would not even have picked him up in the Orphanage. Whatever.

Really, this is interesting! When did the change occur? Is it different in the films and books? Obviously I've read/seen both, but this seems to have slipped my mind! In the films as Tom Riddle in school he looks very normal. When does he mutate

The movie didn't show that. Voldemort wanted to become a teacher of Dumbledore to find Ravenclaw's tiara but Dumbledore said screw you. At that time he looked already very inhuman. He still had hair but already was pale and had red eyes and such. He also had his Death Eaters already. He already began to made Horcruxes. Those were the reason for his change. It was inhuman and split his soul.