Holmes mistakenly surmises that James knows who killed his father and is protecting someone. It emerges that Alice is right about the cause of the argument between James and Charles. What she does not know is that James actually loves her, but could not follow his father's demand because he had married a barmaid before Alice had returned from boarding school. This burdened him, but he could not tell his father about his marriage because he would have been kicked out of the house and left unable to support himself. When his wife heard of his troubles, however, she confessed that she was already married before they met, and therefore their marriage is invalid.