A culprit is arrested in the Jack the Ripper case which was solved by the Moriartys. Suspecting a frame-up by Arterton, Lestrade asks Sherlock for help in finding evidence that would prove it. Meanwhile, Paterson works to sneak Bonde inside the station.

Adam Whiteley, a young MP in the House of Commons working toward an equitable society, garners public support as a "White Knight." Milverton is hired by those opposed to Whiteley to oust him. William takes interest in Whiteley, and decides to test him.