The Scary Thing That Happened To Daniel Radcliffe's Eyes In The Original Harry Potter Movie

They say that eyes are windows to the soul, and that must run doubly true in the fantastic and magical world of the "Harry Potter" franchise. Eyes can be a clue for someone reading your mind through Legilimency or even allow those who have witnessed death to see the misunderstood flying beasts known as Thestrals.

Having donned those famous glasses and that lightning bolt-shaped scar for ten years and eight movies, Daniel Radcliffe could almost be considered the face of the franchise. While in the book series, Harry is described as having green eyes, astute Potterheads know that Radcliffe has blue eyes (meanwhile, Ellie Darcey-Alden, the actor who plays young Lily Evans, Harry's mother, has brown eyes, and the filmmakers couldn't be bothered to make them blue in post-production). Although it wasn't the original intention for Harry to have blue eyes in the film series, it just wasn't possible to make them green.

In 2021, long-time Wizarding World producer David Heyman told Empire (via Wizarding World Digital) a story about how Daniel Radcliffe's physical response to his green contact lenses created movie magic in the last scene of "Harry Potter and the Sorcerer's Stone" (which was the first to be shot).

"I'll never forget being on set that first day, filming the last scene of 'Philosopher's Stone' where Hagrid and Harry bid farewell at the railway station at Hogsmeade," he said. "Dan was wearing these contact lenses to make his eyes green, and he had an allergic reaction to them. His eyes were red and swollen and we had to take them out – we thought we may add that green digitally, though ultimately we decided not to because it felt artificial. But Dan's eyes were puffy and red, and oddly it was quite appropriate for the scene where he was saying goodbye to Hagrid."

According to Icon Eyecare, 1–5% of contact wearers develop an allergy to contacts. This is called secondary giant papillary conjunctivitis and causes redness, itching, and the formation of small bumps on the undersides of the eyelids.

Although the "Harry Potter" crew relented on green contacts and trying to make Daniel Radcliffe's eyes green digitally, this allergy was not the only one the actor had when it came to his iconic look. In a conversation with author J.K. Rowling released on the DVD and Blu-ray editions of "Harry Potter and the Deathly Hallows – Part 2" (via ABC News), Radcliffe shared that he was also allergic to his famous spectacles.

"It was brilliant because we put the glasses on, and eventually, we realized that I was allergic to them," he said. "I was actually allergic to the Harry Potter glasses. Because I had these two rings of whiteheads and spots that had come up around my eyes, and it took us a week to realize that it was actually the glasses."

Although ABC News doesn't share what exactly about the glasses Radcliffe was allergic to, NoNickel.com claims it was the nickel. According to the Nickel Institute, 1–2% of men and 12–15% of women develop an allergy to nickel. This is called nickel allergic contact dermatitis and causes a rash or eczema on the skin. Needless to say, the early production days of "Sorcerer's Stone" must have been quite a field day for the on-site medics, considering that Radcliffe had an allergic reaction to two different parts of his costume.