1 Samuel 28:4-8

So the Philistines assembled and came and camped in Shunem; and Saul gathered all Israel together, and they camped in Gilboa.

When Saul saw the camp of the Philistines, he was afraid and his heart trembled greatly.

So Saul inquired of the Lord, but the Lord did not answer him, either in dreams, or by the Urim, or by the prophets.

Then Saul said to his servants, “Find for me a woman who is a medium, so that I may go to her and inquire of her.” And his servants said to him, “Behold, there is a woman who is a medium at En-dor.”

Then Saul disguised himself by putting on different clothes, and went, he and two men with him, and they came to the woman by night; and he said, “Consult the spirit for me, please, and bring up for me the one whom I shall name for you.”