The Marvel Cinematic Universe is, you could say, kind of popular ... it is a juggernaut, 18-Billion-Dollar film-series with 21 movies to its name and the grand finale, Avengers: Endgame, hitting the big screen about now.
It is set to be the cinematic event of a lifetime ... but let's be honest, you don't remember what happened in Thor 2; nor should you have to. And with time slowly ticking down, you'll need a break from sleep (and eating) to do a full series rewatch.
Luckily, I've got a lot of time on my hands! So here's the story so far. Here goes (deep inhale) ...
Iron Man 
Kicking off this monster franchise was billionaire Tony Stark, who, after being held captive in a cave, created the greatest weapon of all time whilst trying to rid the world of weapons: oh the irony.
The Incredible Hulk 
Iron Man 2 
Tony dates his secretary-turned-CEO, Pepper Potts, and there's a cool spy (Black Widow) and a Spy Agency called S.H.I.E.L.D, which is essentially a less-boring CIA.
Captain America: The First Avenger 
Amidst WW2, Americans pump teenage Steve Rogers with steroids and make him fight Nazis for a magic blue cube.
He develops a relationship with S.H.I.E.L.D founder Peggy Carter and his best friend, Bucky Barnes, falls off a train ... remember this.
Also, he crashes a jet into some ice, freezing him until 2012: where he awakens in a different age ... without the love of his life to console him ... cue the slow-violins.
Thor, the Norse God of Thunder, is banished to Earth to prove his worth. He does.
Also, his brother, Loki, betrays him, falls off a bridge and dies.
Also, also: a guy called Hawkeye has a bow and arrow ... and is supposed to be a top-level Spy ... with a bow and arrow ... in a world of Gods and Hulks ... with a bow and arrow.
Avengers Assemble 
Surprise! Loki didn't die! Now he's trying to take over Earth with an army and a magic stick, thereby accidentally assembling the Avengers - a group of the most powerful heroes of all time ... and Hawkeye.
In a post-credits scene, a Purple-Grape-Man smiles, making nerds everywhere wet themselves.
Iron Man 3 
Tony Stark has PTSD and feels guilty. What fun.
Thor: The Dark World 
An elf tries to destroy the world with some red stuff but fails. Oh, and Loki dies - again.
Captain America: The Winter Soldier 
We learn Nazis are running S.H.I.E.L.D, and like killing people.
Long-story-short: S.H.I.E.L.D goes bye-bye.
Also, Captain America tries to "get it on" with his ex-girlfriend's great-niece, which is really messed up but just roll with it.
Also, also: remember his best-friend from before? Bucky? He's now a mind-controlled cyborg with a robot arm that assassinates people for Nazis. He does, however, save his bestie at the end ... which redeems him?
Guardians of the Galaxy 
Yay, this one is fun!
In order to defeat Space Judge Ronan, a gang of misfits (including a tree called Groot) unite, led by Earthling Peter Quill and Green-Lady-Warrior Gamora, who initially hate each other but discover true love: how original.
Also, the Space-Judge has a magic stone that can destroy planets ... remember this.
Avengers: Age of Ultron 
Guilt-Ridden Tony Stark builds a robot, Ultron, to save the Earth. It then drops a city from the sky: oh the irony.
Also, Black Widow and the Hulk have a *thing*.
Also, also: Loki's magic-stick has a magic stone that's put in the head of a magic-man called Vision.
Also, also, also: Hawkeye now has a family so we can't hate him.
Last also, the Purple Grape Guy puts a glove on, making nerds everywhere pass-out from euphoria.
A guy called Ant-Man exists and can shrink to the size of an ant. And his daughter is adorable. Done.
Captain America: Civil War 
A UN proposal is drafted to prevent any more accidental city-boom-booms caused by superheroes. Guilt-ridden Tony Stark agrees; Steve Rogers doesn't. Smashy-smashy!
The Avengers break up, and Steve's ex-girlfriend dies, and Bucky killed Tony's parents, making him a tiny bit upset.
Doctor Strange 
A doctor hurts his hands and becomes a wizard and gets a time-control necklace.
Guardians of the Galaxy Vol. 2 
Peter Quill's Dad is actually a God, and he kills him because he killed his mum.
Also, Gamora and her half-sister Nebula are rebelling step-daughters of the purple grape man (called Thanos).
Also, also: Groot is tiny and adorable and I want him.
Spider-Man: Homecoming 
Spider-Man is Iron Man's protege, and Tony proposes to Pepper Potts.
Thor: Ragnarok 
Loki isn't dead! But his dad is, and so is Thor's homeworld, his Magic Hammer, his friends, his sister and the relationship had with [GENERIC_LOVE_INTEREST].
But he now has a badass warrior called Valkyrie and a talking blue rock called Korg!
Black Panther 
Wakanda exists. It has a metal called Vibranium. Vibranium does whatever the plot needs it to.
There are also Rhinos.
Avengers: Infinity War 
Purple Grape Man tries to collect all the things (Magic Space-Cube, Red Stuff from Thor: The Dark World, powerful stone from Guardians of the Galaxy, powerful stone in Vision's head and Doctor Strange's necklace). These are called Infinity Stones ... and with them he can snap away half of all life in the universe instantaneously.
Anyway, the superheroes are victori.... Nope. Half of everyone in existence dies. Gone. Forever. Dust, on the floor, to be hoovered away.
Also, Loki IS dead this time ... maybe?
Ant-Man & The Wasp 
Ends with Ant-Man trapped in the Quantum Realm with his closest allies as piles of dust, including his girlfriend Hope - the titular Wasp.
Also, there are time-vortexes... just FYI.
Captain Marvel 
Captain Marvel is quite strong and probably (very, very, very) important.
Avengers: Endgame 
Currently dead and/or prepped-for-hoovering-up characters: Loki, Gamora, Vision, Black Panther, Spider-Man, Doctor Strange, The Winter Soldier, Falcon, Starlord, Drax, Groot, Shuri, Samuel L Jackson (AKA Nick Fury, technically), Scarlett Witch, Mantis, The Wasp + Half of Everyone Else.
Not-Hoovered-Up: Tony Stark is trapped in space with Nebula while the remaining Avengers have adapted to life post-snap, planning - ultimately - to 'Avenge the Fallen'. And just writing that gave me goosebumps.
I hope this little refresher course was in some way useful, and enjoy crying-your-eyes-out in Endgame ... I doubt it will be cheerful.