Eccentric consulting detective Sherlock Holmes and Doctor John Watson battle to bring down a new nemesis and unravel a deadly plot that could destroy England.

A Royal scandal, a dazzling game of cat and mouse. The seductive Irene Adler is cold, calculating, brilliant. Has Sherlock finally met his match?

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.