Warning: HUGE spoilers for Avengers: Endgame ahead!

One of the best elements of Marvel's Avengers: Endgame [1] is the combination of lighthearted fun and devastating heartbreak. With a movie that involves extensive time travel and such high stakes, it can be hard to bring some levity to the big screen. But the film's "time heist," an idea originally pitched by Ant-Man, has some of the best moments in the entire film. It brings us all back to key moments in the Avengers' past and shows us how different everyone is now. 2012's Avengers would most definitely be shaken by their 2023 selves — especially Captain America.

But the time heist doesn't just serve as Marvel fan service, it also drives the big plot of the film. Using the Quantum Realm, that is usually only accessible to the very tiny (aka Scott Lang and company), the Avengers travel back in time to collect the six Infinity Stones [2] and recreate Thanos's snap. Instead of dusting the universe, they snap all their "dead" loves ones [3] back to life. They might be missing the last five years of their lives (since the film jumps in time to 2023), but they're alive and that probably matters more.

Of course, there are specific rules to follow when it comes to time travel [4] and Endgame abides by most of them. The biggest and most important rule is that The Avengers aren't supposed to re-write the past, they're only setting out to create a different future [5]. As with all things that start out with the best intentions, things don't go exactly the way they plan. Keep reading for our handy guide to the Avengers' quest for the Infinity Stones as they travel back in time and then back to the future.

• The purple Power Stone, aka the Orb: This stone is originally introduced in Guardians of the Galaxy when the Guardians defeat Ronan the Accuser, who attempts to use the Orb to destroy the planet Xander. Nebula and Rhodey are assigned to travel back to the planet Morag in 2014 and retrieve the stone right before Peter Quill is meant to steal it. The mission itself is fairly seamless, with Nebula reaching straight into the lasers surrounding the Orb and taking it out. They kind of burn off the flesh(?) on her arm, but it's robotic so she's totally fine! However, as soon as War Machine teleports back to the future, Nebula is attacked and kidnapped by the 2014 versions of herself and Thanos. This leads to the past version of Thanos travelling through time to battle for the Infinity Stones and destroy half the world all over again in 2023.
• The blue Space Stone, aka the Tesseract: Though this Infinity Stone was originally on Asgard with Thor and his family, it's been seen on Earth several times over the years. In Endgame Tony and Scott are assigned to travel back to 2012, right before the end of the first Avengers movie where Thor brought the Tesseract back to Asgard, along with Loki. Scott flies into 2012's Tony heart and causes him to go into cardiac arrest so he'll drop the briefcase containing the Tesseract. The plan is for future Tony, dressed in a SWAT team uniform, to sneak by and grab the suitcase, but he's swatted when an angry Hulk crashes into him. Seeing his chance, Loki snatches the fallen briefcase and uses the stone to teleport away.
  Tony and Steve then head to New Jersey in 1970, where the Tesseract is being held and Hank Pym is working on Pym Particles. While Steve grabs the particles, Tony steals the Tesseract. He runs into his father, Howard, and the two share a sweet moment commiserating on fatherhood with Howard blind to the fact that Tony is his son. Tony and Steve return to 2023 with the Infinity Stone and more particles to allow a trip to return the stones in the end.
• The yellow Mind Stone: First seen in The Avengers as part of Loki's Chitauri scepter, the mind stone isn't actually revealed to be an Infinity Stone until Avengers: Age of Ultron. Steve is sent to 2012 to grab the scepter from the S.H.I.E.L.D agents (actually undercover Hydra agents) who took it from the Avengers after they apprehended Loki. Steve follows the agents into the lift and pretends to also be an undercover Hydra agent (a nice little shoutout to the Marvel comics run) so they'll give him the scepter. He has a brief — but epic — one-on-one fight with 2012's Captain America, before handing the scepter off to Scott, who returns to the future. Steve then travels with Tony back to 1970 to find more Pym Particles, allowing for more quantum leaps. While he's there, he sees Peggy Carter, which most likely inspires his decision to return to her [6] at the end of the film.
• The red Reality Stone, aka the Aether: Introduced in Thor: The Dark World, the Aether is more like a substance than a stone. Thor and Rocket travel to collect the Aether from Asgard where Jane Foster (remember Jane!?) has become it's host in 2013. While Thor is distracted by the presence of his late mother Frigga, who gives him a rousing pep talk to help him feel better about the events of Infinity War, Rocket is able to sneak into Jane's room and use an extractor tool to take the Aether from her.
• The orange Soul Stone: First referenced in Guardians of the Galaxy, the Soul Stone is the most mysterious of the Infinity Stones. As revealed in a conversation between Thanos and Gamora in Infinity War, the stone's location is on the planet Vormir and protected by the Red Skull. Natasha and Clint travel back to 2014 to get the stone, not knowing that a soul is demanded in exchange for it. After a very dramatic back-and-forth, Natasha sacrifices herself [7] for the stone and Clint returns to 2023 without the Black Widow [8].
• The green Time Stone, aka the Eye of Agamotto: Introduced in Doctor Strange, the Eye of Agamotto is protected by the Master of the Mystic Arts, Doctor Stephan Strange, and kept in a secret compound, Kamar-Taj. Bruce is sent to 2012 to grab the stone from Doctor Strange, but he doesn't actually live there yet. Back then, the Time Stone is in the possession of the Ancient One who refuses to hand it over. The Ancient One explains that giving it to Bruce could create alternate branched realities, which are worse than the current one. But when Bruce reveals that Doctor Strange willingly gave the stone to Thanos, the Ancient One concludes that this must be part of the 1 in 14 million chance Doctor Strange saw in his vision. Bruce gets the stone under the promise that the Avengers return them all to the exact the moment in time from which were taken.

With all six stones, the Avengers are able to snap back their dusted friends and families [9]. But before everyone can live happily ever after, the Avengers go to battle with the past version of Thanos. It ends when Tony steals the stones from Thanos and into a makeshift gauntlet built into his suit. He snaps his fingers and wills away Thanos and his army, who all disintegrate the same way people did in Infinity War. Tony's snap burns up his body and he dies on the battlefield [10] with his wife, Pepper, and protégé, Peter Parker, at his side.

At Tony's funeral, the Avengers are finally united with their loved ones and go about their lives. Steve takes the remaining Pym Particles to return the stones to their own timeline and decides to use his last time jump to go back and live a happy life with Peggy. Sam and Bucky find a much older version of Steve [11] waiting for them near the lake, where he explains his decision and passes on the Captain America shield to Sam. With that, Marvel fans officially say goodbye to the Infinity Saga [12] of the MCU.