Flossie Birdwhistle is the Turnkey at London’s Highgate Cemetery. Seven years have passed since Flossie saved her country from a ghostly invasion during World War II. Since then, things have been quiet. That is, until Flossie’s nemesis, Hugo Howsham, reveals a secret the pair have been keeping - the keys of the Magnificent Seven cemeteries can be combined to make a Turnkey not only mortal, but immortal.

When Hugo Howsham begins stealing keys, the other Turnkeys turn against Flossie, trusting her no longer. With family, friends and her cemetery in danger, can Flossie find the inner strength to protect everything she has ever cared about?