Herbie and Violet's fifth gripping adventure brings the internationally bestselling Eerie-on-Sea series to a heart-stopping climax.

It is Midwinter once again, and a group of cryptozoologists have descended on the town to investigate the unresolved mystery of the malamander's long-lost mate. Herbie and Vi don't see what harm they can do, but as the monster-hunters begin to make new discoveries, the pair become uneasy. Then the fury of the malamander is roused, and the two friends experience a terrifying encounter deep beneath the earth. One that may lead them to finally discover the Deepest Secret of Eerie-on-Sea…