A plain envelope of good quality, addressed to the Head of the Werewolf Wing. Inside:
a typed note bearing an E.L.F. (Eradicate Lycantrophy Foundation) letterhead and written in a fussy style
Dear Madam,
I write to inform you of a highly illegal establishment by the name of Lapin, that serves to harbour and even CELEBRATE unregistered werewolves in the United Kingdom.
You may find one of its entrances at 1600 hours every Tuesday and Thursday, by going through the Out of Order stall in the gentleman's bathroom of the Electric Ballroom in Camden Town, London.
Be aware that I intend to inform several publications of this establishment, which makes a travesty of public safety and decency, should the Ministry fail to take appropriate action. I have after all done all the real investigative work for you.
Yours Faithfully,
A Concerned Friend.