While anticipation for an Avengers movie was sky high, not even the combined brains at S.H.I.E.L.D. could have predicted just how popular the film would end up being. Making a phenomenal $1.5 billion worldwide, it became the most successful superhero film of all time and, thankfully, was also really really good.
With the sequel mere months away, here's a look back at 15 things you might not know about The Avengers.
As well as providing a rather obvious boost to Marvel's brand globally, the film also helped the sales of shawarma. The finale boasts an offhand line about the food from Tony Stark and then the end credits features the whole team enjoying a truckload of the stuff. The weekend of release saw unprecedented sales of the Middle Eastern delicacy in LA, with one place noting an 80% rise.
The film initially achieved an R rating in the US which would have meant that anyone under the age of 17 needed an elder to accompany them. The reason? Agent Coulson's death. "Well," Marvel chief Kevin Feige explained, "whenever you impale somebody from their back and the blade comes out of their chest, there are issues."
After a somewhat successful, yet brief, stint as Bruce Banner in The Incredible Hulk, Marvel decided not to invite Edward Norton to be part of The Avengers. Norton was keen to be involved and met with director Joss Whedon to discuss the project but after proving difficult behind the scenes of the 2008 movie (he allegedly battled over the final cut), he was taken out of the equation. "Our decision is definitely not one based on monetary factors, but instead rooted in the need for an actor who embodies the creativity and collaborative spirit of our other talented cast members," Marvel honcho Kevin Feige revealed, rather bitingly.
In the original script, Joss Whedon also included Ant-Man and The Wasp as they are both founding members of the team in the comics. At the time, Eva Longoria was rumoured to be playing The Wasp.
The film was being shot close to Breaking Bad in Albuquerque and Samuel L Jackson was keen to shoot a cameo role. As he is close to Giancarlo Esposito, who played Gus, he wanted to walk into Los Pollos Hermanos, buy chicken and leave. He claimed that the producers of The Avengers told him there was no time.
There was a discussion between Sony and Disney to include Oscorp Tower from The Amazing Spider-Man in the Manhattan skyline of The Avengers. Both sides were in agreement about it being a damn awesome idea but by the time the work on the Oscorp visuals had been done, it was too late and the Avengers effects had been finished.
Even though the film has a whopping $220 million budget to play with, one rather interesting cost was cut. During the hangar fight between Thor and Hulk, the fighter jet that breaks Hulk's fall was the same one used in True Lies.
Interestingly, Mark Ruffalo was actually director Louis Leterrier's first choice to play Bruce Banner in his 2008 reboot The Incredible Hulk. He claimed that he was told by Marvel to get Edward Norton because "he's more famous."
Joss Whedon initially wanted there to be two villains as he didn't believe that Loki would prove enough trouble to keep all of the team occupied. But Marvel rejected the idea.
Joss Whedon had initially hoped to film it all in 3D but he found the equipment "so weird" so conceded and allowed a post-conversion to happen instead.
Scarlett Johansson had to turn down a role in the Total Recall remake because of her commitments to The Avengers. Lucky escape.
Natalie Portman was set to reprise her role as Jane Foster for a cameo in the film but she became pregnant and her baby ruined everything.
Gwyneth Paltrow was originally not supposed to be in the film but Robert Downey Jr insisted the character of Pepper Potts had some screen time so Joss Whedon wrote a small but memorable scene. Apparently, it was also Downey Jr who pushed for an expansion of her role in Iron Man 3 as well.
In her recent reality show Lindsay Lohan claims that she was close to getting a part in the film but her manager didn't push enough for the role. She claims that the part was given to an "unknown" but didn't confirm which character she could have been.
And back to the shawarma. The final final post-credits scene where the team enjoys a much-needed middle eastern meal was only shot after the film premiered in Los Angeles.