Over 5 years, humans have been at war with an alien species called the mimic. NATO military have to create a federation of United Defense Forces (UDF), with a whopping increase as the war continues. As imitate tighten their grip in Europe, the patenting of mechanical exoskeletons allow UDF to achieve a decisive victory at Verdun. Major William Cage, UDF spokesman and officer in the U.S. Army Reserve, was called to London to meet with General Brigham, commander of the UDF. UDF, inspired by the victory at Verdun, intends to launch Operation Downfall, the invasion front Mimic multi-controlled Europe that will relieve the pressure on Russian forces in Eastern Europe and China. Brigham Cage orders to cover the fighting in the Northwestern coast of France, which is the object Cage, stating that he was not a soldier. When Cage tries to squeeze the General, he was arrested and stripped of rank Cage. Cage sent to the base at Heathrow Airport, where he was to deploy from the following morning. The next morning, Cage was dropped by the first wave. To his horror, which mimics have anticipated the attack, and destroy the invasion force. Cage managed to kill Mimic, but died when he was splashed with blood. Cage woke up earlier in the morning at Heathrow, and debriefed the same way. Cage find he was trapped in a time loop, and that each time he dies, he "reset" for the day before the invasion. Cage tries to convince the soldiers at the base that the invasion would fail, not succeed. Cage loop several times, trying to save many soldiers as he could. In one circle, he saves the life of Rita Vrataski, "Angel of Verdun", who, seeing Cages ability to anticipate events of the battle, tell him to find when he "woke up." Both were later killed by a transport plane exploded. At the base, Cage discovered Rita, and told him that they know each other from invasion in the next day. Rita admitted in a Cage that he also has the ability to "reset", which allows him to mimic alone kill hundreds in Verdun, earning him celebrity status. Rita told Cage that mimic controlled by a single consciousness called "Omega", which has the ability to reset the time. When Cage watered by the blood of certain Mimic, known as the "Alpha", he gained the ability to "reset." Rita failed to kill Omega after receiving a blood transfusion in Verdun, causing him to lose his power to "reset". He also said that Cage as imitating trying to find his consciousness, he would experience a vision of the Omega site. Rita train Cage in battle, and with each loop, the next Cage improvement in capability. Rita and Cage team during the invasion, and after dozens of loops, finally able to make their way into the interior. Cage, meanwhile, have grown attached to Rita, and found it more difficult to see him killed. Tensions reached a head when Cage tries to stop Rita from continuing, knowing that in their current location, Rita be killed off. Rita ignores him and severely injured trying to take off the helicopter. Cage comfort when he died, before he was killed by a mimic. During the next cycle, Cage, knowing that Omega is in the Bavarian Alps, go for the kill Omega itself. When he arrived at the dam of his vision, he was ambushed by Alpha, which is trying to steal back his ability to kill him. Cage died by drowning, preserving ability. During the next cycle, Cage told Rita that vision just a ploy to corner him and stole his ability. Rita took Cage to see Dr. Arthur, a former government scientist and expert on biological Mimic. Arthur tells Cage that during his time working in Whitehall, he built a prototype transponder device, which theoretically can ascertain the location of the Omega if injected into the Alpha or someone with a "reset" capability. General Brigham oversee the development, but said garbage and has dismissed Arthur. Rita and Cage to infiltrate the Ministry of Defense, and threatened to kill Brigham unless he gave them the transponder. After a few loops fail, Brigham relented and gave them a transponder. Whitehall blurred with soldiers in pursuit, Rita stabbed Cage with transponders, and he concluded that Omega is located under the Louvre. Cage eliminate transponders, but Rita rammed an armored soldier, knocking them both unconscious. Cage woke connected to an IV, and realized that the transfusion had taken power. Rita Cage breaks out, and they decided to try and kill Omega same night. To do so, Cage assured of army units to join them, already knowing the intimate details of their lives from its loop. The team flew to Paris, but was attacked by imitating and forced into an emergency landing. Rita and Cage is the only one to make it under the Louvre, where they find themselves hunted by Alpha. Rita gives Cage belt grenades to kill Omega, then kissed him, told him "I just wish I could get to know you." Rita while the Alpha distract Cage diving down to kill Omega. The Alpha kill Rita, then dive down after Cage. The Alpha killed him, but not before he activates a grenade belt, which falls on Omega, killing it, thus crippling emulate. As Omega destroyed, Cages body absorbs the blood. Cage woke up on the way to a meeting with Brigham, and he attended a press conference where Brigham announced that mimics seems to have given up and that the UDF is ready to liberate Europe. Cage, never revoked rank, visited Heathrow base, and went to see Rita. Rita asks who he is, having never met him, smiling Cage.
