"Sir,” he said, looking Mr. Utterson in the eyes, "Was that my master’s voice?” "It seems much changed,” replied the lawyer, very pale, but giving look for look.

"Changed? Well, yes, I think so,” said the butler. "Have I been twenty years in this man’s house, to be deceived about his voice? No, sir; master’s made away with; he was made away with eight days ago, when we heard him cry out upon the name of God; and who’s in there instead of him, and why it stays there, is a thing that cries to Heaven, Mr. Utterson!”

"This is a very strange tale, Poole; this is rather a wild tale my man,” said Mr. Utterson, biting his finger.

One advantage to having this excerpt told from a limited third-person point of view is that the reader

knows all the characters’ thoughts, which removes confusion.
knows both Jekyll’s and Hyde’s thoughts, which boosts the horror.
only knows Jekyll’s thoughts, which creates a sense of mystery.
only knows what Utterson and Poole know, which builds suspense.