"The Man Who Read
John Dickson Carr,"
by William Brittain
In this story, Edgar
decides to emanate his
idol, the mystery
novelist John Dickson
Carr, by committing a
locked room murder
that would be worthy of
a mystery novel.
He would have pulled it off too,
except for one very important
detail: he forgot to lock the
door.
In Brittain's story we can see
the use of means, motive, and
opportunity as Edgar schemes
to commit the perfect crime
(one that he cannot be found
guilty for).
What is the only possible
perfect crime?
Motive

We know he has a motive to kill his
uncle (excluding Edgar from his will),
and so does his uncle's lawyer and
doctor.
Means
We also know that he is a grown man
who is physically able to kill his uncle.
 He had knowledge of the chemical
reaction to start the fire after he went
up the chimney.

Opportunity
So in order for Edgar to get away with
murder he must cast doubt on his
opportunity to commit the murder by
creating a locked room scenario.
 If he couldn't have gotten in or out of
the room, how could he have killed his
uncle?

All of his preparations where to
prove that he did not have the
opportunity to kill his uncle.
He cleaned the chimney, and wore all
white clothes.
 He hid the sword in the corner.
 He got the chemical paper to light a
fire after he escaped through the
chimney.

All this was so that the two
witnesses could not possibly
place him at the scene of the
crime regardless of his obvious
motive or means.
Yet all of his efforts were futile,
being that he forgot to lock the
door.