221 B. Baker St. Watson is feeling frustrated by Sherlock's messiness but, Sherlock tell him about the Musgrave Ritual.
They introduce the butler, Brunton and he's a ladies man. Brunton was engaged to Rachel Howells. Rachel got sick and Brunton dumped her. Brunton soon goes missing after being fired from his job. He gets fired for looking at secret documents, The Musgrave Ritual.
They go out to find Brunton by solving the riddle that leads to the Musgrave Manor. They solve it, an it leads them directly to the back door of the old house and they walk in.
They walk down to the cellar and find a stone door with an iron ring on it. They open the door and find the lifeless body of Brunton, the butler. He was lying there in a pool of his own blood.
Sherlock suspected that, there was one of two ways Brunton could've died. His first theory was that, Rachel killed him. Brunton broke up with her and has done her wrong so, she would be an obvious choice when he went missing. His second theory was that this all was an accident.The wood slipped and crushed Brunton, the door was too heavy for her too lift. Thinking she would of got charged for murder she ran off overseas.
Brunton's lifeless body wasn't the only thing they found in the cellar. They found the crown of Charles the second, as well. They solved the riddle of the Musgrave Ritual and it lead them to the crown. King Charles the second unfortunately died before he could tell anyone where he held it for all these years. By solving the riddle it lead them right to it.