Enola Holmes is back for one final mystery, and she faces a deadly foe - from the series that inspired the films, starring Millie Bobby Brown.

When Enola Holmes hears a muffled clanging sound coming from a ''safety coffin'' in a chilly cemetery, she follows the sound to a crudely dug fresh grave. She starts digging...and inside a coffin she finds a girl who is drugged but not quite dead.

But how to find where the girl belongs - or where she is running from - when she can''t remember anything about who she is? Only Enola could persevere to solve the mystery, in the face of a gang of heavies on her trail and her brother Sherlock''s strict warning to stay away from the case.