Before Leto can form an alliance with the Fremen, the Harkonnens launch their attack. The Harkonnens' traitor within House Atreides, Dr. Wellington Yueh (Leto's personal physician), disables critical shields and destroys sonic weapons, leaving the Atreides nearly defenseless. Idaho is killed, Leto is captured, and nearly all of House Atreides is wiped out by the Harkonnens. Baron Harkonnen has Mentat Piter De Vries kill Dr. Yueh with a poisoned blade. Leto dies in a failed attempt to assassinate the Baron Harkonnen using a poison gas tooth implanted by Dr. Yueh. After being wounded by Yueh, Leto let him install the tooth in exchange for sparing the lives of Lady Jessica, his concubine, and Paul.