Department M is ostensibly a task force or group within the Special Branch of the Metropolitan Police. Waggish rumor has it that the "M" stands for "Midsummer," as in Shakespeare's play of Fairy Politics, A Midsummer Night's Dream.

The group consists of approximately twenty individuals, though there are three main "field agents" -- Lillian Salisbury, Octavia Debenham, and Quince Dunboyne. The remaining individuals provide support services for investigations.

The group is headed by Sir Roger Avebury. It is headquartered (alone) in "Old" Scotland Yard in Whitehall; the rest of the Metropolitan force has just moved to "New" Scotland Yard on the Embankment.

Ill Met By Gaslight