The Guardians of the Galaxy respond to a distress call from the Asgardian ship and rescue Thor, who surmises Thanos seeks the Reality Stone, which is in the possession of the Collector on Knowhere. Rocket and Groot accompany Thor to Nidavellir, where they and Eitri create a battle-axe capable of killing Thanos. On Knowhere, Peter Quill, Gamora, Drax, and Mantis find Thanos with the Reality Stone already in his possession. Thanos kidnaps Gamora, his adoptive daughter, who reveals the location of the Soul Stone to save her captive adoptive sister Nebula from torture. Thanos and Gamora travel to Vormir, where Red Skull, keeper of the Soul Stone, informs him the stone can only be retrieved by sacrificing someone he loves. Thanos reluctantly kills Gamora, earning the stone.