On the morning after the discovery of the murdered man's body, the two
officers made their way to Tanton Gardens from the Hampstead tube
station. Inspector Chippenfield was a stout man of middle age, with a red
face the colour of which seemed to be accentuated by the daily operation
of removing every vestige of hair from it. He had prominent grey eyes
with which he was accustomed to stare fiercely when he desired to impress
a suspected person with what some of the newspapers had referred to as
"his penetrating glance." His companion, Rolfe, was a tall well-built man
in the early thirties. Like most men in a subordinate position, Rolfe had
not a high opinion of the abilities of his immediate superiors. He was
sure that he could fill the place of any one of them better than it was
filled by its occupant. He believed that it was the policy of superiors
to keep junior men back, to stand in their light, and to take all the
credit for their work. He was confident that he was destined to make a
name for himself in the detective world if only he were given the chance.

When Inspector Chippenfield had visited Riversbrook the previous
afternoon, Rolfe had not been selected as his assistant. A careful
inspection of the house and especially of the room in which the tragedy
had been committed had been made by the inspector. He had then turned his
attention to the garden and the grounds surrounding the house.

Whatever he had discovered and what theories he had formed were not
disclosed to anyone, not even his assistant. He believed that the proper
way to train a subordinate was to let him collect his own information and
then test it for him. This method enabled him to profit by his
subordinate's efforts and to display a superior knowledge when the other
propounded a theory by which Inspector Chippenfield had also been misled.

When they arrived at the house in which the crime had been committed,