Mum in the dark on Bret McKenzie's new gig with James Corden

Kiwi Bret McKenzie and late night host James Corden have been in the recording studio. But what they've done is still a mystery, even to McKenzie's mum. Photo / AP

Even the mother of Kiwi comic Bret McKenzie doesn't know what he and The Late Late Show star James Corden are cooking up.

British funny-man Corden took to Twitter yesterday to post a photograph of himself and McKenzie in a recording studio, but the teaser didn't detail exactly what the pair were up to.

Loved being in the studio with Brett McKenzie last night! What a guy! X pic.twitter.com/3Xila6nA0u

— James Corden (@JKCorden) July 29, 2016

When the Herald contacted McKenzie's mother Deirdre Tarrant, she said she was currently with her son in the US but didn't know what he was working on with The Late Late Show host.

"I'll ask him. We're about to go for a walk."

She said McKenzie and Flight of the Conchords co-star Jemaine Clement had just completed a nationwide tour in the US.

Corden's Carpool Karaoke skit, which appears in The Late Late Show, has been a hit with fans all over the world, with guests including Michelle Obama, Jennifer Lopez and Elton John.

Music is also the basis of McKenzie's highly acclaimed work.

As one half of comic band Flight of the Conchords with Jemaine Clement, the Kiwi duo's self-named TV series was picked up by major US network HBO and was also a hit in the UK.