Season one sees Dirk and Todd wind their way through one big, seemingly insane mystery, crossing unlikely paths with a bevy of wild and sometimes dangerous characters, each episode landing them a few random steps closer to uncovering the truth.

When a chance encounter brings soldier John Watson into Sherlock's life, it's apparent the two men couldn't be more different, but Sherlock's intellect coupled with John's pragmatism soon forges an unbreakable alliance as they investigate a series of baffling cases together.

Sherlock is back, but will things ever be the same again?