1 Samuel 28:11-12 KJV
Then said the woman, Whom shall I bring up unto thee? And he said, Bring me up Samuel. [12] And when the woman saw Samuel, she cried with a loud voice: and the woman spake to Saul, saying, Why hast thou deceived me? for thou art Saul.
Why is everybody assuming she was "shocked"? And "frightened" by the apparent arrival of Samuel? It just says she cried out with a loud voice and was scared ABOUT THE FACT THAT HER CLIENT WAS SAUL. Nothing about being spooked by a ghost. Her crying with a loud voice just means she yelled. Looks to me like she was more upset about having Saul for a client than having Samuel for a seance.