While official synopsis for "Avengers: Age of Ultron" is yet to be revealed, possible story details emerge online teasing the first 15 or 20 minutes of the film. According to Latino-Review, the opening set piece is a big action scene [Spoiler Alert!] that involves Baron Von Strucker (Thomas Kretschmann).
The second Avengers movie will reportedly pick up directly after the credit scenes in "Captain America: The Winter Soldier". The Earth's Mightiest Heroes attack the Hydra outpost run by Baron who fights back with the help from Quicksilver (Aaron Johnson) and Scarlet Witch (Elizabeth Olsen).
He has Loki's staff, possesses Chitauri weaponry, and has the corpse of a leviathan. The Scarlett Witch uses her powers and casts a spell on the Hulk (Mark Ruffalo) into thinking that the Leviathan is still alive. The superheroes eventually beat the trio and head to the Avengers Tower to celebrate their victory.
They allegedly take turns trying to pick up Thor's hammer Mjolnir. The arm of Tony Stark's (Robert Downey Jr.) armor falls off when he tries to pick it up in his Iron Man suit, while Captain America can only shift it a bit but still can't pick it up. According to the leaked plot, Rhodey (Don Cheadle) is also among the partygoers.
The sequel will show the blossoming relationship between Hulk and Black Widow (Scarlett Johansson). He is afraid to consummate their romance out of fear that he could accidentally hurt her. Things between Thor (Chris Hemsworth) and Jane Foster (Natalie Portman) are not good either. At one point, the Asgardian knight sits at the bar watching her with Richard (Chris O'Dowd's character from "Thor: The Dark World").