Tom Hiddleston's character, Loki, in the Marvel Cinematic Universe has always been a bad guy through and through. He's a primary antagonist to Thor and nearly brought the Earth to extinction in "The Avengers." There are rumors that fans will be seeing a new side to Loki in "Thor: Ragnarok" and "Avengers: Infinity War," but it appears that viewers may have already seen hints showing Loki playing a hero in disguise.
First we take a look at Loki's character. In the first "Thor" movie, Thor was portrayed as the arrogant brother and desperate to prove himself as a worthy successor to his father, Odin (Anthony Hopkins). Loki was the calmer brother, and in "Thor: The Dark World," it was seen that Loki dearly loved his mother.
A theory suggests that his plans were made for the better good. First, Loki was able to win Thanos' trust and earned the scepter from him. It's a great deal to win the trust of The Mad Titan, but he was able to do so. In Thanos' hands, the scepter with the mind stone in it could've dealt a much bigger blow to every race in the Universe. Perhaps by taking possession of it, Loki was doing everyone a favor. Perhaps Loki has always known that Thanos was hell bent on destroying the universe, and he must have taken some of the Infinity Stones to lessen Thanos' chances of succeeding.
The Battle of New York is also part of Loki's plans to thin down Thanos' army. By leading the Chitauri army to Earth, he led them straight to the Avengers which took down their entire fleet. With the Chitauri gone, the Avengers have one less problem to contend with.
"Avengers: Infinity War" is said to show the third act in Loki's plan. Naturally, Thanos will be looking for him and seeking to punish him for failing in his so-called plans.
In a previous interview with Entertainment Weekly, Hiddleston gave a piece of information from the set of "Thor: Ragnarok." "It is actually a fight day tomorrow. I don't think I'm fighting specifically him, however. Spoiler alert! But that's all I will tell you," Hiddleston said, which perhaps hints that he wouldn't be fighting Chris Hemsworth's Thor, but will be fighting alongside him.
Cate Blanchett is playing Hela, the main villain in "Thor: Ragnarok" and its possible Thor and Loki will band together to defeat her. Speaking to IGN, Hiddleston explained that the brothers have not seen the level of terror Hela brings in her wake, so they "fall back on their brotherhood, fractured though it is, to see what they can do to stop her."