The Scarlet Witch and her brother Quicksilver have reluctantly joined Magneto's Brotherhood of Evil Mutants in his plans to rule the Earth when she became in debt with the master of magnetism who saved her from the superstitious inhabitants of a small European village. Soon, the team takes over the small Republic of San Marco and submits its inhabitants using fear. The Scarlet Witch uses her mutant magic ability at generating chaos to help defend Magneto's new castle against the X-Men. But she is appalled by her leader's decision when he is willing to sacrifice the population of San Marco to destroy the X-Men with a large bomb.
The Brotherhood of Evil Mutants once more engage in battle against the X-Men who force them to escape from their space station.
Gambling on the hypothesis that he might be a mutant and the knowledge that he wants to dominate the surface world, Magneto offers Namor an alliance. During an attack by the X-Men, the Sea Prince sees how Magneto treats the Scarlet Witch and he chooses not to ally himself with him. The Evil Mutants are forced to escape.
Looking for a way to defeat the X-Men, Magneto finds the Blob in a circus but the carnies get into a fight with his Brotherhood of Evil Mutants. The Blob refuses to join Magneto until a concussion brings his memory of the X-Men back. During a fight against the X-Men, Quicksilver and the Scarlet Witch are appalled that Magneto was willing to sacrifice the new recruit to destroy his enemy, which causes the fat mutant to quit the team.
Magneto sends his Brotherhood on a search for the X-Men but when they find them, they realize that they no match and run away.
Wanda has a very realistivc dream about the Black Knight being in great danger. After some investigation she is teleported to Arkon's dimension alongside Pietro, Clint and Vision. There, they are able to defeat Arkon and Enchantress and rescue the Black Knight.
Wanda unknowingly lands on Earth-712 and has a vision of it being destroyed by the sun. After learning the possible reason for the cataclysm, he and his fellow stranded Avengers beat the Squadron Surpreme and fly off to stop the catastrophe.
Growing tired of Magneto's evil, Pietro wants to run away with his sister, but Wanda reminds him of their promise to Magneto. They finally decide to ask advice from the Fantastic Four at the Baxter Building. Due to their reputation, the Human Torch and the Thing welcome them as criminals and the encounter turns into a fight. Realizing that going there was a mistake, the two mutants return to Magneto.
Wanda listens as T'Challa tells of his origin.
She is present at the Avengers-Meeting.
During a battle against the X-Men, the Stranger offers Magneto to flee with him, which he does. After Cyclops helps her brother who has been frozen by Iceman, the Scarlet Witch declares that she will never serve Magneto again. The X-Men offer them to join their team, but she and Quicksilver prefer to stay out of conflicts and go back home in Central Europe.
Learning in the papers that the Avengers are recruiting members, Quicksilver convinces the Scarlet Witch that they should apply since being an Avenger won't be a constant reminder that they are mutants. Once in America, they are greeted by Tony Stark and accepted as new members of the Avengers.
The new members of the Avengers get a visit from Thor, but their first encounter is not very cordial.
As the Avengers are searching for the Hulk to add muscle to their team, they fall into a trap set by the Mole Man and find themselves in the pit of the Minotaur which they defeat. The Mole Man then decides to send them back to the surface before they destroy him too.
The Avengers travel to Sin-Cong to free its people of their Red tyrant, the Commissar, who turns out to be a robot controlled by the Communist army.
After hearing Cap's tale of the Greymoor Castle, Wanda wonders if he got trouble for deserting his platoon. Cap tells his friends that high ranking officers knew about his secret identity and made up a cover story for his absence. When Hawkeye asks him about Bucky's fate, Wanda observes that Cap is still heavily burdened by the death of his partner.
Quicksilver and the Scarlet Witch take down the Swordsman who has intruded the Avengers Mansion pretending he wants to join their team. After he escapes, the Swordsman, who carries quite a bad reputation internationally, uses Captain America's interest in being part of Nick Fury's team to lure him into a trap. His teammate track him town to a warehouse where the villain threatens to push their capture friend down a building if they don't make him leader of the Avengers. But Cap jumps off before they agree. With teamwork, they manage to save him. Then while they fight the Swordsman, their foe suddenly vanishes. Back at their headquarters, they get a message from Iron Man saying that he vouches for the Swordsman's membership so they decide to take his word and give the man a chance. Some time later, Cap and Hawkeye catch the Swordsman apparently setting a bomb, but the villain escapes with the bomb which detonates outside their HQ,
The Avengers experience some weird events where their interventions are perceived by the press as criminal. With more and more incidents involving them, the authorities force the Avengers to disband, and due to their already conflictive relationship, they part in bad terms. Wanda tries to find a job in show-business, but due to the recent bad press, the only man to open the door is the Ring Master who welcomes them among his carnies. But the hypnotist's attempt to convince them to pillage the audience fails so the former Avengers engage combat and defeat the Masters of Menace. The Ring Master calls the police, forcing his troublesome recruits to flee. Thanks to Captain America' trick to get Power Man confession on tape and after Princess Python has admitted the truth to the D.A., the authorities reinstate the Avengers' status and even decide that an official Avengers Day will be held. But later, Captain America tells his teammates that he's quitting anyway.
The Scarlet Witch blames Hawkeye for his attitude that led to Captain America's leaving the team. Kang captures the remaining Avengers and takes them to his own century. The Scarlet Witch sets them free from their glass cages and despite Kang's effort, the Avengers reunite with Cap who has found a way to track them down. Realizing that Kang intends to overthrow the current king and marry Princess Ravonna, the Avengers choose to side with the people. They convince the king's army to fight back, but Kang manages to take over anyway. Kang's refusal to slay the conquered princess provokes a rebellion amongst his commanders and the conqueror gets the help of the Avengers to stop the war and save the princess in exchange for their safe return to their century.
Getting a letter from an aunt in Latveria, Wanda and Pietro are thrilled at the idea of finally meeting someone in the family who can tell them about their parents. The other Avengers decide to accompany them, but it's all just a trap set by Doctor Doom who seals the land within a giant dome right after their arrival. Their joint effort enables the heroes to lift the dome away and escape.
