Spoiler Warning: This article contains some spoilers for Avengers: Endgame. Enter at your own risk!
There are plenty of memorable lines in the MCU that fans love to quote, and Avengers: Endgame definitely makes some contributions to the list. The one that might go down as the most memorable, however, is "I love you 3000," which sent fans reaching for their tissues. Well, you better grab some more because it was Robert Downey Jr. who added the line, and its origins are incredibly sweet.
Okay, it's time for the unavoidable spoiler. In Avengers: Endgame, Tony Stark has a daughter with Pepper Potts named Morgan Stark. The little five-year-old is maybe the most precious thing in the movie, and she serves as a major influence on Tony's arc in Endgame.
During one scene between the father and daughter early on in the film, Morgan tells Tony "I love you 3000." It's super cute and it turns out that the line was actually one of Downey's. According to co-writer Christopher Markus, RDJ added the line because it's something that his real-life children actually say to him.
Well, as much as we'd like to take credit for what is inevitably going to be one of the most memorable lines in MCU history, that is something that Robert and his children actually say to each other. He brought it from real life onto the set.
Markus told Fandango that the line was partly Robert Downey Jr.'s based on his relationship with his children. The original line was supposed to be "I love you tons." That makes the moment in the film all the sweeter and it probably helped Downey a little bit with his performance, too.
That makes the line a little more touching, too, because it's ultimately the very last line that Tony Stark says in the movie. As a father and as the guy who helped start the whole MCU, it must have been a nice moment for Downey.
Only time will tell if "I love you 3000" goes down in MCU history as the greatest line, but Endgame has lots of other memorable lines as well. Whether it's Thanos giving another menacing monologue or Captain America's "whatever it takes" (and "America's ass"), MCU fans have lots of options when it comes to quotes to say forever.
Seeing as how the film is about to pass $2 billion in only its second week in theaters, you've probably already seen it. In case you haven't, Avengers: Endgame is in theaters right now and you better see it today because the spoiler ban apparently ends tomorrow. If you've already seen Marvel's epic blockbuster, you don't have to wait too long for more films to hit theaters. Check out our 2019 movie release guide for everything that's coming down the pipeline.