Cosmo, a witch-cat, is delighted that evil Sybil - the most terrible of witches - is safely in prison. In fact, she's even fitted with a special tag, which means that if she and her cronies try to escape they will be turned into frogs.

But then mysterious goings-on are reported in Witch News. Baby witches are being visited by a strange new health visitor - and having their long, curly toenails clipped and stolen! Something sinister is afoot. Could it be that Sybil and her criminal cauldron are at work again?

This book has been graded for interest at 7-9 years.

There are 192 pages in this book. This book was published 2008 by Pan Macmillan .

Gwyneth Rees has written under different names for many best-selling children's series, but Mermaids is her first work for Macmillan. When she's not writing, Gwyneth is a psychiatrist in a London hospital. She lives in west London with two cats.