The following day, the pair find that the flag they had planted is missing. Having completed their mission, the duo prepares to leave, but the launch is aborted when Liberty suffers violent shaking. An inspection reveals extensive damage to the module. Walker finds their shredded flag nearby; the motion sensor camera is also missing, and the rover tipped on its side. He then finds non-human tracks outside Liberty, and cites them as evidence of extraterrestrial life. Walker feels something moving inside his spacesuit and is horrified as a spider-like creature crawls across the inside of his helmet; he disappears from view and Anderson finds him unconscious outside of Liberty. Walker later denies the events. A wound is discovered on his chest, and Anderson removes a Moon rock embedded within him. After having removed the rock, Walker smashes it with a hammer, contaminating the ship. The pair find themselves unable to contact Houston or Grey due to increased levels of interference from an unknown source. Anderson speculates that the true purpose of the "ICBM warning device" is to monitor the aliens, and that it is the source of the interference. Anderson and Walker attempt to switch the device off, only to discover it has been destroyed, with the same non-human tracks surrounding it. Walker shows signs of a developing infection, such as vein discoloration (possibly caused by necrosis) and blood-shot eyes, and he becomes contentious and paranoid. The mission cameras capture a rock sample moving around in the interior of Liberty, revealing that the aliens are camouflaged as Moon rocks. Increasingly delusional, Walker attempts to destroy the cameras within Liberty with a hammer, but he accidentally damages other controls, causing Liberty to depressurize. Realizing the Soviet LK lander is their only source of oxygen, the pair travel to the LK lander in their Lunar rover. Walker becomes agitated, believing he should not leave the Moon because of the risk of spreading the infection to Earth, and causes the rover to crash. As the rover crashes, the camera catches glimpses of the large space rocks, which begin to grow legs similar to that of spiders. Anderson awakens and tracks Walker to a crater. Walker is pulled into the crater by the creatures. Anderson gives chase, but he is confronted by the aliens, and flees to the Soviet LK and uses its radio to contact USSR Mission Control, who connect him to the