In this double-length first episode a young Sherlock arrives home unexpectedly from boarding school, he finds his parents gone and a mystery at the manor house.

Sherlock investigates Natty Dan's death.

Tom Hudson helps Sherlock with the mystery of "Old Mo".

This episode has no summary.

This episode has no summary.

Sherlock and John Whitney are in grave danger.

This episode has no summary.

This episode has no summary.