This is a prequel to the Frost series but written by a different author as RD Wingfield died.  I think it does keep the general character of Frost fairly well.  The story is not quite so dark as I remember the original Frost stories to be but nonetheless I do think it is a good addition. 

Julie Hudson is 12 and trying on a new school uniform when her mother leaves her to look in the lingerie department.  Upon her return she discovers her daughter is missing.  Another woman reports that her daughter has been bitten by a fox and may have developed rabies.  In amongst all of this DI Allen is away on holiday and DI Bert Williams has disappeared leaving Frost to deal with the problems and Superintendant Mullet