*SPOILERS BELOW*

If you haven't yet seen the reunion episode - turn away now. If you have, then please, read on.

Whether you're a fan or not, 'Friends: The Reunion' is all that everyone will be talking about today. And for good reason - we really enjoyed our trip back through the 10-season sitcom with our six friends.

Seeing Jennifer Aniston, Courteney Cox, Lisa Kudrow, Matt LeBlanc, Matthew Perry, and David Schwimmer back together again 17 years later was quite a wholesome affair. However, there was one moment featuring one of the cast that will remain one of the best moments of the special.

Lisa Kudrow adopted her Phoebe persona one final time for a sing-along to her hit song 'Smelly Cat'. However, she's not about to sing this one alone, and the one and only Lady Gaga arrives in to help with the task.

Wearing an outfit that Phoebe Buffay would be proud to wear, in struts the global superstar with her guitar, and the pair begin a powerful rendition of the track. They're later joined by a gospel choir, and it all comes together very nicely indeed.

Afterwards, Lady Gaga then turns to Lisa to thank her for playing a character that so many people relate to. She says: "Thank you so much for being the person for all of us on 'Friends' who was, I don't know if this is the right way to say it, but the different one, or the one who was really herself."

While the appearance of Lady Gaga on the special might seem a bit "out there" it will no doubt go down as one of the highlights of the episode. It doesn't take away from the episode, but rather elevates the whole experience for the viewer.

'Friends: The Reunion' is available to watch via Sky or streaming service NOW.