Avengers Endgame released on 26th April 2019 was about Avengers(those who survived the snap) reuniting together & doing the Time Heist with a motive to reverse Thanos’ snap in order to bring back the dusted ones. We will try to understand time travel theory along with the Avengers journey during time heist in Avengers Endgame through this article.
The Time Travel in Avengers: Endgame is based on a popular time travel theory in the field of quantum physics. Post Thanos’ snap the remaining Avengers(those who survived the snap) learnt that Thanos destroyed the stones after completing his mission this means that Avengers won’t be able to use the Infinity Stones again & reverse his snap. They were a bit taken aback & disappointed, in rage Thor even chopped off Thanos’ head.
Five Years Later, at present (i.e.2023) It was because of a rat Scott Lang was able to get out of Quantum Realm(To understand more about the quantum realm & how did Scott ended up there you need to watch Ant-Man and the Wasp) as soon as he learnt exactly what happened (Thanos’ snap) when he was in the Quantum Realm he went to the Avengers compound, there he met Natasha & Steve, & explained them his experience of the quantum realm, he tries to explain that time moves differently in the quantum realm further explaining that he was in it for five years according to the world but it was just five hours for him. He then suggested that they can travel back to a different point of time using the quantum realm & try to reverse Thanos’ snap. But since the three of them didn’t have the exact knowledge of quantum physics they thought to get help from Tony Stark, but Stark refused to help as doing time travel & changing the present would also risk his family, especially his daughter Morgan’s existence. So after Tony’s refusal to help Natasha, Steve along with Scott approached Banner who was now a merged version of his intellect with Hulk’s physique. They tried the time travel experiment using Stott’s Van which kind of didn’t go well. Steve who was disappointed with the failure of the time travel experiment went out of the Avengers compound, just then Stark approaches him with time-space GPS, he also returns Steve his shield back indicating his reunion for the plan of time travel.
Time Heist plan Execution
The remaining Avengers assemble at the Avengers compound, Banner & Rocket went to New Asgard to recruit Thor for Time Heist however they’re met with the now overweight, depressed, drunk Thor, On the other side Natasha goes to Tokyo to stop Clint Barton from the massacre he has been carrying on in vengeance after losing his family in the blip & tells him about their time heist plan, Stark along with Rocket builds the time machine & suits, they run a time travel test & Barton volunteers himself for it, it was successful. Now, they plan to travel back in time and retrieve the Infinity Stones from various points in history before Thanos collects them & does the snap.
Time Travel to Collect Infinity Stones from Different Places and Timelines
Hulk, Ant-Man, Iron Man and Captain America were sent back to the Battle of New York in 2012, where Hulk was sent to the New York Sanctum to request the Time Stone from Doctor Strange, but there he met The Ancient One, initially she refused to give the Time Stone explaining that she could not give him the Infinity Stone so Banner could alter his timeline and subsequently leave hers undefended without the stone, However when Banner told her about Doctor Strange giving up the Time stone voluntarily, trusting Strange’s decision she agreed to give the Time stone to Banner, as he also promised that he would return the stones at the exact moment it was taken, erasing the dark splinter reality that will be created due to absence of the stones.
On the other side, Steve was able to acquire Loki’s Scepter (it contained mind stone) from STRIKE by pretending to be associated with HYDRA, STRIKE (Special Tactical Reserve for International Key Emergencies) was a counter-terrorist Special Mission Unit of S.H.I.E.L.D., it included several of S.H.I.E.L.D.’s best agents, however at the same time most members of the team were actually undercover HYDRA Agents, On the other side, Stark & Lang tried to steal the Tesseract, but failed as Loki got a hold of it & used it to teleport himself. So Stark and Rogers decided to go back further to Camp Lehigh to an alternate 1970 New Jersey, there they tried to grab the Tesseract and more Pym Particles for their further journey. Lang is left with the Scepter to return to the present day. Steve was able to get more Pym Particles but he sneaked into a cabin, to avoid Agent Jenkins as she had considered him and Tony suspicious and reported them, soon he realized it was Peggy Carter’s cabin(his love) who was also S.H.I.E.L.D. director at that time he silently watches her from far & even Stark was able to get Tesseract but when he was about to leave from there he encountered Howard Stark (his father), Tony introduced himself with the name Howard Potts, they had a brief conversation & Tony was able to finally get a chance to give his father a hug & thank him.
Meanwhile, Thor & Rocket went in an alternate timeline 2013 in Asgard to remove Aether(Reality Stone) from Jane Foster’s Body. While they were there Thor saw his mother Frigga & got emotional as after some time according to the original timeline Frigga is killed, Thor was trying to hide but Frigga caught him she also knew that he is from future, they had a conversation & she advised him to follow his own path. He tried to warn her about her upcoming fate (death) but she refused to hear him & accept her fate rather than changing it. Rocket arrives with Aether & Thor hugs his mother last time, but before leaving from there he summons his hammer Mjölnir, he is also relieved at the fact that he is still worthy of it & takes the hammer along with him.
Ronin, Natasha, Rhodes & Nebula went to Morag with Benatar in the 2014 timeline, Rhodes & Nebula wait for Peter Quill as he would lead them to collect the Power Stone Orb from Morag, Rhodes knocks out Quill & they took the orb, but as they prepare to return to the present timeline together only Rhodes shrinks back into the Quantum Realm, Nebula’s cybernetics glitch & she falls to the ground, she is left behind as affected by the connection with her alternate past self, due to this connection Thanos of the past timeline(2014) gets aware about his future(his snap & death) & also Avengers Time Heist plan. As soon as Nebula realized it she tries to inform other teammates but the alternate past Nebula captures Nebula of the present timeline & travels to the present time through the quantum realm.
Natasha & Ronin further went to Vormir in Benatar to get the Soul Stone, They are greeted by Red Skull, stating that he knows them “Natasha, daughter of Ivan” and “Clint, son of Edith”, and warns them about the sacrifice of a soul(loved one) is to be done in order to obtain soul stone. Both Clint & Natasha were ready to sacrifice their own life in order to save the other one, However at the end, Natasha jumped off the cliff by her own will despite of Clint’s attempt to stop her, he then wakes up with the soul stone in his hand in the pool of Vormir but cries in grief due to Natasha’s death.
After completing their mission to collect stones from different timelines they all return to the present time(2023) & the fellow Avengers learn about Natasha’s sacrifice they were shocked & sad to lose her but they also determined not to let her sacrifice go in vain & decided to move further with their plan & do the snap. Hulk wielded the Infinity Gauntlet & did the snap but the radiations of the Infinity Stones damaged his arm. Although their mission to bring back the dusted one’s was successful. However, they hardly got time to celebrate their victory as Thanos(from the 2014 timeline) attacked them by teleporting himself along with his army with the help of Nebula. All the Avengers(including the dusted ones) assemble & give a tough fight to Thanos & his army(Battle of Earth), but Thanos acquires the gauntlet of Infinity stones & was about to do the snap once again but Tony tries to stop him, the Mad Titan knocks Tony aside & did the snap but nothing happens as Tony transferred the stones into his suit & does the snap wiping out Thanos & his army resulting in Avengers victory but Tony dies shortly after doing the snap due to the radiations of the Infinity Stones.
Return of the Infinity Stones
After winning the Battle of Earth & attending Tony’s funeral Steve travels back in time through the Quantum Realm to return the Infinity stones as promised also Thor’s hammer Mjölnir, and returns the Infinity Stones to the exact moment it was taken, erasing the dark splinter reality that was being created due to their absence.
After returning the Stones he decided to remain in past & live his life along with Peggy Carter & return as an old person, he also brought the shield that he gave to Sam Wilson (Falcon) passing him the baton of Captain America.
The Movie Culture Synopsis
Time travel theory in Endgame is a popular time travel theory in the field of quantum physics. So If Avengers tried to change something in past (like kill baby Thanos: as suggested by Rhodes), as explained by Banner (Professor Hulk)it wouldn’t affect the present timeline it would just create a parallel timeline different from the original timeline where the snap is already done. So there was no use even if they stopped or killed Thanos as this wouldn’t reverse his snap that already happened.