Elly Griffiths for The Frozen People

Elly Griffiths makes her much-anticipated return to Bath to celebrate the paperback release of The Frozen People: the first book in a brand new series from the author of the bestselling Dr Ruth Galloway mysteries.

If you're missing Ruth and Nelson, wait till you meet Ali and Cain.

Ali Dawson is a police officer working on crimes so old, the joke goes, that they are not only cold but frozen. What most people don't know is that the team travels back in time to complete their research - a process pioneered by the mysterious Italian physicist, Serafina Pelligrini.

So far the team has only ventured a few years back but Ali's boss has a new assignment for her. He wants her to step back to 1850, the heart of the Victorian Age, to clear the name of Cain Templeton, the eccentric great-grandfather of Tory MP Isaac Templeton.

To prepare for the challenge ahead, Ali researches the Victorian era. She learns that Cain Templeton was part of a sinister group called The Collectors, the rumour being that you had to kill a woman to become a member. Duly prepared, she arrives in London in January 1850, at the peak of the so-called mini ice age, to start her journey in a house used by artists, with a dead woman at her feet.

Soon she finds herself in extreme danger. Even worse - she appears to be stuck, unable to make her way back to the present, to her life and to her son, Finn.