Scripts, diaries, and letters from the life and career of Alan Rickman are set to go up for auction at the ABA Rare Book Fair in London. In addition to Rickman's personal scripts from Robin Hood Prince of Thieves and Die Hard, there are also personal letters that reveal the late actor's frustrations with his Snape character while working for 10 years on the Harry Potter franchise. There are letters to Alan Rickman from Harry Potter creator J.K. Rowling as well as a letter from producer David Heyman that highlight that things weren't always awesome behind-the-scenes.

One of the letters that has gained the most attention is from Harry Potter producer David Heyman, who sent Alan Rickman a letter to thank him for working on the second film, The Chamber of Secrets. In the letter, Heyman thanks Rickman for helping to make the movie such a big success. He then addresses that fact that the late actor was at times frustrated with decisions that were made for his Snape character. Heyman had this to say.

"Thank you for making HP2 a success. I know, at times, you are frustrated but please know that you are an integral part of the films. And you are brilliant."

Alan Rickman later wrote a note while working on the 2009 movie The Half-Blood Prince. Rickman titled the letter as "Inside Snape's Head," and wrote about the frustration over the way director David Yates approached Snape's storyline. Rickman didn't believe that Yates was doing the Snape character justice, and instead insinuates that the director was pandering to a younger audience. He said.

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"It's as if David Yates has decided that this is not important in the scheme of things i.e. teen audience appeal."

A letter that Harry Potter creator J.K. Rowling sent to Alan Rickman is also in the large collection. In the letter, Rowling thanks the late actor for, "doing justice to my most complex character." After Rickman passed away in 2016, the author revealed that she told him "what lies behind the word always," which was deeply important for Rickman since only a few books had been written at the time of the first Harry Potter movie. Alan Rickman learned early on that Snape was a complicated character and that everything wasn't so black and white.

Creative differences are bound to happen during practically any project, especially when it's franchise as big as Harry Potter. Alan Rickman's thoughts and frustrations seem like they were always rooted in doing what was best for the Snape character and revealing the depth of the human. Regardless, all of these letters, scripts, and diaries are going to go up for auction at the ABA Rare Book Fair in London and is rumored to be worth nearly a million dollars. You can read more about Alan Rickman's personal collection of correspondence going up for auction at Independet U.K.