The duo were joined by Aaron Dessner of The National too, who produced their song 'Exile'.

Let's set the scene: you're in London's Wembley Arena enjoying the calming sweet-nothings from Bon Iver, when out pops Taylor Swift to bring the house down. Oh, and Aaron Dessner is also on stage giving it socks. And then you collapse into a heap because it's all just too much to handle.

But yes, this really happened in London last night to some very lucky fans. Justin Vernon of Bon Iver began singing the track alongside The National's Dessner when Swift made her surprise appearance. The trio performing on stage at the one time made the OVO Arena Wembley erupt into deafening screams from fans in attendance.

'Exile' is a collaboration between Taylor Swift and Bon Iver, which appears on her album 'Folklore'. Dessner was also a producer on the song, which received a nomination for Best Pop Duo/Group Performance at the 63rd Annual Grammy Awards in 2021. Dessner also collaborated with her on some tracks from her new album 'Midnights'.

Here's the moment Swift walked out on stage from various angles/screaming levels.

Taylor Swift is currently riding on the wave that is her newest album 'Midnights'. The tenth studio album from the pop star was released last Friday with two different editions - the '3am Editions' features seven new tracks, three of which Aaron Dessner co-wrote and co-produced. Swift also worked with Lana Del Ray on the track titled 'Snow on the Beach'.

Bon Iver performed at Dublin's 3 Arena earlier this month. A 10-year anniversary edition of 'Bon Iver' was released earlier this year featuring some new live recordings.