Bob Mortimer has revealed the title and plot of his second novel, a mystery.

Provisionally called The Long Shoe, he disclosed that he only has 20 pages of it still to write on last night's episode of The One Show, appearing alongside his Gone Fishing co-star Paul Whitehouse.

The story is "about a bloke who's wife leaves him but maybe she's been taken, he's got to find out" Mortimer explained. "On the way he utilises a very long shoe to solve the mystery. It's a great book!"

When fellow guest Greg Davies questioned this, asking, "have you written it Bob? Because it sounds like you're making it up", Mortimer protested: "Honestly!"

The comedian first revealed that he was writing a second novel in May, following the success of his debut The Satsuma Complex. He told Kathy Burke on her Where There's A Will, There's A Wake podcast, that he would not be reviving his semi-autobiographical, disaffected legal assistant character Gary Thorn from the first novel.

"I thought if I did the same character, I'll just write the same book," he said. "So I thought, you know, go do something different."

The Satsuma Complex is being published in the US on Tuesday but with its name changed to The Clementine Complex.

Mortimer's publishers Simon & Schuster could offer no reason to British Comedy Guide for the name change. However, it seems likely to be chiefly alliterative, as satsumas tend to be sold as tangerines in the States.

Mortimer & Whitehouse: Gone Fishing returns for a sixth series on BBC Two on Sunday. Mortimer has also just penned the foreword to How We Fish: The Love, Life And Joy Of The Riverbank by Whitehouse and the show's fishing consultant John Bailey, published 14th September by Mudlark.