Lost River: A Rivers of London casefile

Someone’s started burning wicker men in Battersea park.
The first slid neatly into HOLMES 2 as “public vandalism, minor”, as 10 square feet of Battersea turf is not what police careers are made of.
But after last night’s burning it is now Operation Letterbox and possibly a career maker.
Three corpses have been found in the ashes, thus the new characterisation of the incident as “murder, possibly cult/sectarian” requires a full Falcon Assessment.
Your team is called on to investigate this crime, and its wider implications for the powerscape of the Thames River Valley.
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