William Hartnell was a very interesting Doctor. When asked the famous question, "Doctor Who?", he responded "Precisely". He was an older and grumpier Doctor, but also rather wise in some occasions. Even very sentimental. The 10th Doctor stated that at this point in his life, he was trying to be all old and important.
His companion Susan, was also rather adorable, I think.
Second Doctor: [link]
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