"I feel like a Carpool Karaoke reject," says Eddie Redmayne, clambering into a van full of balloons alongside James Corden in the clip above.

Their task, which involves travelling across LA to surprise people with telegrams, does have a fair bit in common with Corden's most popular series from The Late Late Show, too — there's driving, there's singing, and there's plenty of entertaining conversation in between.

Still, Redmayne has something none of the Carpool Karaoke stars have: balloons. 

So, so many balloons. Read more...