Voice in darkness. Thorne A.

A new case for the commissar and consultant: the corpse of a girl was found in the park, whose face is disfigured so that it is impossible to identify her. At first glance, nothing otherworldly, but soon Longsdale discovers a trace of strange magic, the nature of which cannot explain, and after the first victim there are also the following...

The danger is also threatened by Margaret - the restless niece of the commissar.