歇洛克·福尔摩斯的药物成瘾的根源来自他的内心,在自己和华生医生的努力下,他暂时摆脱了毒品。可是,问题并没有消除,只是潜伏下来了,并且潜伏得很深。在第三季季终,福尔摩斯不幸复吸,其父听闻这一消息后赶往纽约。华生则在丧偶后回到福尔摩斯身边。While Sherlock awaits for the D.A. to decide if he's going to charge Sherlock for aggravated assault which he did recently. And his father is coming which he dreads. A man approaches him and it turns out to be a man who's suspected of killing three women one of whom is his wife whose body was never found. He tells Sherlock he didn't kill his wife while he killed the other two women. He then shoots himself. Sherlock then decides to investigate the wife's disappearance. He discovers that the woman is from Honduras and another girl also from Honduras went missing at around the same time she did. So he thinks there must a link.