Ollie wasn't quite expecting to meet the actor in a pub of all places, but it was the perfect opportunity to pose for a quick photo.
Celebrity Big Brother star Ollie couldn't have looked happier as he grinned from ear to ear. Meanwhile Kunal, who appears to be in London with his wife Neha Kapur, also looked pretty happy to be meeting a fan of the show!
Kunal plays the loveable - but also slightly awkward - astrophysicist Raj Koothrappali in the hit US comedy.
Captioning the snap, Ollie said: "Casual Sunday night In the pub with @kunalnayyar - Raj from The Big Bang Theory! Such lovely guy!"
Lots of fans commented on the pic, including Adam Pitts from pop rock band Lawson. He said: "This is awesome, Raj is a hero!"
Ollie soon replied: "Adam... Just calmed down!! Far too excited, acted like a proper fan girl!!"
We love watching The Big Bang Theory in the UK, and we can expect to see plenty more of it on our screens, as in March CBS renewed the sitcom for three seasons due to the show's immense popularity.
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