Gandalf leads Aragorn, Legolas, Gimli, and King Théoden to Isengard where they reunite with Merry and Pippin. With Saruman defeated, Gandalf retrieves Saruman's palantír. Overcome by curiosity, Pippin steals a glance into the seeing-stone, and suffers a mental attack from Sauron himself. Gandalf deduces that Sauron will attack Gondor's capital Minas Tirith, so he rides there to warn them, taking Pippin with him because Sauron thinks Pippin is the ring bearer.