Bullets and high-speed chases, gadgetry and superhero trash talk: The newly released trailer for Marvel's "Avengers: Age of Ultron" promises fans of the franchise more of what they love about its first installment, 2012's "The Avengers."

The star-studded sequel isn't set to hit movie theaters until May 2015, and the trailer offers a first glimpse at what Joss Whedon will do with the story about the Marvel supervillain. The 50-year-old director, whose efforts behind the camera helped the first movie gross $1.518 billion, last year told a Comic-Con audience that "Age of Ultron Ultron" would be "a little bit darker than the other film."

"It's got a sci-fi element to it that's a little bit stronger than the other film. Getting the team together was so rousing. But seriously, keeping the team together is a completely different problem," Whedon said, according to MTV.

The movie centers on the aftermath of the destruction of the espionage agency S.H.I.E.L.D. Robert Downey Jr.'s character Tony Stark, alias "Iron Man," tries to enlist the self-aware, self-teaching artificial intelligence Ultron in a peacekeeping mission. The latter, however, turns against humans and tries to wipe them from the face of the earth. Iron Man and his band of fellow superheroes must once again work as a team to save the fate of the planet.

Beside Downey, "Age of Ultron Ultron" features Chris Hemsworth as Thor, Mark Ruffalo and Bruce Banner-turned-Hulk. Appearing, as well, are Chris Evans as Steve Rogers, aka Captain America, and Scarlett Johansson as Natasha Romanoff/Black Widow.

Vanity Fair recently dubbed Downey "the world's highest-paid actor," in no small part thanks to the "Avengers" movies. The 49-year-old told Collider that he does not feel he has fallen into a trap with the franchise; despite the action, the story has room for depth and great acting, he argued.

"I love these kinds of movies," Downey said. "So I feel like I'm just a very tolerant kind of consumer with these things. But ... I think that there has to be a bit of a transcendence of formula." And "without giving too much away," the actor concluded, viewers notice that as early as in the first scene.