Ian McKellen has embarked upon a surprise tour of Windsor with one of his fans.

Millie Anna went to see him perform in The Cherry Orchard at Theatre Royal Windsor -  and McKellen spotted her post about it.

The Lord of the Rings star approached the 17-year-old and asked her to give him a tour of the town which lasted for four and a half hours.

Anna, who runs a personal Instagram blog about her life with Down's Syndrome, happily agreed and documented her journey on social media.

She also featured on BBC Breakfast today (8 November) to talk about the experience and what it was like meeting McKellen.

She said: “I just think what he does is spectacular. I love that he has good energy… he is iconic.

“We went to Windsor Castle, we went to the cobbles, we went to my favourite restaurant, Enzos.

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“We had pasta and pizza. He was amazing and really fun to be with.”

She added that the way McKellen communicated with her was “spot on” and Millie’s father, Jeff, added that he was “an incredibly kind man”.

Millie said: “I want to be an actress and hopefully just like Ian. Make sure you believe in yourself, love yourself and forgive yourself too.”

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In an Instagram post, Millie Anna said: “Ian saw my post when we went to see 'The Cherry Orchard' at the theatre in Windsor.

“He messaged me to ask if I'd like to show him around town. I was so excited! We had such a fun time, we talked and laughed as we went to all my favourite places. I'm so lucky he chose me to be his tour guide - it was just the best day ever.

“I laughed - he made me feel so special! What a day.”

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Ian added that his own cousin also has Down’s Syndrome.

On his own Instagram page, Ian wrote:  “I chanced on a photo of the 17-year-old Millie Anna outside the Theatre Royal with Martin Shaw and me in the background.

“It turned out Millie Anna is an aspiring model and outspoken about Down’s Syndrome. I had a cousin with the same condition. Now she has shown me around Windsor, under the loving guidance of her father Jeffrey, who snapped us on our way.”

In the pictures, the duo can be seen exploring the roads and posing in front of Windsor Castle.

Ian also posed alongside Millie next to a poster of a missing cat.

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The caption reads: “A cat has either gone missing from or has escaped to Windsor Castle.

“I hope by now he's returned home, but if you happen to see Wolfgang out and about please comment below.”

Ian’s followers love the Instagram snap and have praised the pair for sharing the unexpected day out.

One person wrote: “You are such a beautiful soul to present this other beautiful soul to us and give her your spotlight”.

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“She is wonderful and hopefully with more positive platforms like this Millie and girls just like my daughter can have a chance to go after their dreams just like everyone else!” another added.

Simon Burke added: “Can’t wait to see you shine on stage. You’re amazing Millie, hope you enjoyed your guided tour Ian.”

To keep up-to-date with Mille Anna’s adventures, visit her Instagram page, @outwith_millieanna.