Demelza and the Spectre Detectors

Demelza loves science – she loves it so much that she’s been known
to stay up late to work on her peculiar inventions! But Demelza
discovers she has inherited a distinctly un-scientific set of skills:
Spectre Detecting. Like her grandmother, she can summon the
ghosts of the dead. But when Grandma is kidnapped by a mysterious
villain, she knows Spectre Detecting has something to do with it.
Only Demelza and her pasty best friend, Percy, can solve the deadly
mystery …