'Thor: Ragnarok' release date, plot and cast news: Thor asks for Loki's help to locate his father?

The sequel to 2011's Marvel-based superhero movie, "Thor" and 2013's "Thor: Dark World," is already slated for a Nov. 3, 2017 release date, and is officially titled "Thor: Ragnarok."

The upcoming Marvel movie is gaining much more hype because it would also include Doctor Strange, who is played by Benedict Cumberbatch, in a newly released film. In addition, fans can't wait for Cumberbatch to star alongside Tom Hiddleston, who plays Loki in the "Thor" franchise.

From the title itself, many fans speculate that the movie will focus on the events, or on the cycle of Ragnarok, which Thor (Chris Hemsworth) must stop from happening in order to not destroy his home world, Asgard.

It is also speculated that Thor will ask for Loki's help in order to locate his father, Odin (Anthony Hopkins), who was banished as a homeless man in New York City. Thor apparently needs him to stop the seemingly inevitable Ragnarok.

Meanwhile, further speculations also suggest that the upcoming "Thor: Ragnarok" will reveal the "H" in the T.H.A.N.O.S. theory. It is believed that "H" will stand for Hela, goddess of the spirit of the dead, and a character to be played by Cate Blanchett.

Hela is expected to be able to control souls and spirits through a Soul Stone, and possibly another Infinity Stone, some of which had already been revealed through previous Marvel-based movies. Furthermore, it is speculated that Hela might lose her Soul Stone to Thanos in "Thor: Ragnarok."

In the recently released "Doctor Strange" movie, the "N" in T.H.A.N.O.S. is believed to be the "necklace," which referred to the Eye of Agamotto.

Aside from Hemsworth, Hopkins, Hiddleston, Cumberbatch and Blanchett, the movie also stars Idris Elba as Heimdall, Mark Ruffalo as Hulk, Tessa Thompson as Valkyrie, Jeff Goldblum as Grandmaster, Karl Urban as Skurge, and Sam Neill in a still unnamed role.