Severus Snape
In "Harry Potter and the Order of the Phoenix", the fifteen-year-old Snape (portrayed by Alec Hopkins) makes a brief appearance in a flashback to Snape's youth. In the final film, "Harry Potter and the Deathly Hallows – Part 2", the younger Snape, perhaps ten or eleven, is played by Benedict Clarke. In 2016, a fan film prequel, "Severus Snape and the Marauders", was released online and Snape was played by Mick Ignis.