Após os eventos em Thor (2011) , onde Loki caiu da ponte de cristal, como mencionado no Wikia MCU ,
Loki, devastated by Odin's repudiation of his actions, let go of Thor on purpose and fell into the abyss made by the destruction of the Bifrost Bridge.
Ele caiu no Wormhole e ...
..arrived in a part of the universe called Sanctuary and met the Mad Titan Thanos, who offered a pact that would allow him to become ruler of the Earth while he would take the Tesseract which was being studied by S.H.I.E.L.D.. Thanos provided Loki with a Scepter with a blue gem which acted as a powerful weapon, and also as a mind control device.
Depois disso segue os eventos em Os Vingadores da Marvel (2012) .