'Avengers: Infinity War' release date, cast news, plot updates: Nebula slated to appear in film; Peter Dinklage cast in a key role

The upcoming "Avengers" film is expected to expand the story to different Marvel worlds, and Nebula, portrayed by Karen Gillian, might be appearing from one of them. Meanwhile, "Game of Thrones" actor Peter Dinklage has been tapped to play a key role in "Infinity War."

Gillian, who appeared as the evil adopted sister of Gamora (Zoe Saldana) named Nebula in "Guardians of the Galaxy," has been confirmed to reprise her role in the upcoming "Avengers: Infinity War" film.

In an interview with BBC, Gillian shared the projects that she will be involved in this 2017, which are "The Circle," "Guardians of the Galaxy, Volume Two," and "Jumanji."

The actress then added, "And then I'll be making a little appearance in the next 'Avengers' movie."

The big bad that the Avengers will be facing in "Infinity Wars" is Thanos, which is Nebula and Gamora's adopted father, so her presence in the title is expected to be related to the villain's storyline.

Slashfilm reports that in "The Infinity Gauntlet" comic series, Nebula played a vital role where she was among the first few victims of Thanos' rule using the Infinity Gauntlet that was composed of the six Infinity Stones.

But there is no news whether "Infinity War" will pattern its storyline with the comic series.

Meanwhile, Variety has confirmed that "Game of Thrones" and "X-Men: Days of Future Past" star Dinklage will be appearing in a key role in the upcoming "Infinity War" film.

It is anticipated that "Avengers: Infinity War" and its sequel will be shot back-to-back, and Dinklage's character is set to be involved in both titles. However, details about his character are being kept under wraps.

ComicBook speculates that Dinklage will appear as the spearhead of Advanced Ideas Mechanics (AIM): Modok, also known as the "Mobile Organism Designed Only for Killing."

"Avengers: Infinity War" is set to premiere on May 4, 2018.