Read the excerpt from The Strange Case of Dr. Jekyll and Mr. Hyde. Well, sir, the two ran into one another naturally enough at the corner; and then came the horrible part of the thing; for the man trampled calmly over the child’s body and left her screaming on the ground. It sounds nothing to hear, but it was hellish to see. It wasn’t like a man; it was like some damned Juggernaut. I gave a few halloa, took to my heels, collared my gentleman, and brought him back to where there was already quite a group about the screaming child. He was perfectly cool and made no resistance, but gave me one look, so ugly that it brought out the sweat on me like running. How is Mr. Hyde characterized in the excerpt?