7 Days In Hell trailer: Kit Harrington and Andy Samberg have made a tennis mockumentary and it looks hilarious

John McEnroe and Serena Williams remember the 'legendary match'

Game of Thrones's Kit Harrington and Lonely Island's Andy Samberg have teamed up for a Spinal Tap-esque mockumentary about a seven-day tennis match called 7 Days In Hell.

Flamboyant 80s hair and headbands abound, the pair play tennis stars Aaron Williams and Charles Poole, whose gruelling match sees clothes shredded and arms broken.

John McEnroe and Serena Williams provide insight along the way, along with fictional tennis experts played by, among others, Will Forte, who steals the trailer with a tremendous bit-to-camera.

EW describes Samberg's character as a 'mulletted troublemaker', while Harrington's is a 'dim-witted prodigy'.

It's an interesting change for Kit, who is usually seen staring into the distance from the Wall in Game of Thrones.

Lena Dunham, Karen Gillan, Michael Sheen, Mary Steenburgen, Howie Mandel, Fred Armisen, and June Squibb will also make appearances in the mockumentary.

7 Days In Hell premieres on HBO on 11 July in the US.

@christophhooton