[Alf]

When Alfred Hitchcock was a child (5 or 6 years old) his father sent him down to the Police station with a note. When he gave the note to the Policeman at the desk, the Policeman put young Alfred into a Police cell and left him in there for five minutes. When he let him out, he told young Alfred "this is what happens to naughty boys" from that day on, Alfred Hitchcock had a fear of Policemen.

It was Alfred's fathers way of teaching young Alfred not to misbehave.