At the end of book 17 of the Roman Mysteries, Caroline Lawrence introduced us to Threptus - a young beggar boy. In this fun and fabulous new series, Threptus starts work with his mentor - the soothsayer, Floridius - and together they must solve their first mystery...

Can they rid a rich woman's house of the demon that haunts it in the dead of night? What is the true nature of the demon? And is it really a supernatural being?

Threptus is a brave, funny and loveable hero and each story is a mini-mystery perfect for readers aged 7 up.