1 Samuel 28:6-8
28:6 So Saul inquired of the Lord, but the Lord did not answer him – not by dreams nor by Urim nor by the prophets.
28:7 So Saul instructed his servants, “Find me a woman who is a medium, so that I may go to her and inquire of her.” His servants replied to him, “There is a woman who is a medium in Endor.”
28:8 So Saul disguised himself and put on other clothing and left, accompanied by two of his men. They came to the woman at night and said, “Use your ritual pit to conjure up for me the one I tell you.”