Utterson–Guest relationship

Mr. Utterson, the lawyer, maintained a close professional relationship with his head clerk, Mr. Guest, a man of counsel and a great student and critic of handwriting. Utterson kept fewer secrets from Guest than from any other man, and was not always sure he kept as many as he meant. Guest had often been on business to Dr. Jekyll's house, knew the butler Poole, and could scarce have failed to hear of Mr. Hyde's familiarity about the house; he might draw conclusions. It was this combination of trust and Guest's expertise that led Utterson, after receiving Hyde's letter, to consider showing it to his clerk in the hope that Guest's remark might shape his future course.

The Handwriting Analysis

One evening, Utterson sat on one side of his own hearth with Guest upon the other, a bottle of a particular old wine between them. The lawyer introduced the subject of the Carew murder case, and Guest remarked that the man, of course, was mad. Utterson then produced Hyde's letter, describing it as "a murderer's autograph." Guest's eyes brightened, and he studied it with passion, concluding that the writer was not mad but that the hand was odd. Just then, a servant entered with a note from Dr. Jekyll—an invitation to dinner. Guest asked to see it, and the clerk laid the two sheets of paper alongside and sedulously compared their contents. After a pause, Utterson asked why he had compared them, and Guest replied that there was a rather singular resemblance: the two hands were in many points identical, only differently sloped.

The Consequences of the Discovery

Utterson acknowledged the observation as "rather quaint," and Guest agreed. The lawyer then instructed his clerk not to speak of the note, and Guest replied, "No, sir. I understand." But no sooner was Utterson alone that night than he locked the note into his safe, where it reposed from that time forward. The implication was devastating: "Henry Jekyll forge for a murderer!" And his blood ran cold in his veins. Guest's expert analysis had provided the first concrete evidence linking Jekyll directly to Hyde, a connection that would haunt Utterson for the remainder of the story.