"The Avengers: Age of Ultron" film director Joss Whedon has revealed what fans should expect from actors James Spader, Elizabeth Olsen and Aaron Taylor-Johnson in joining the blockbuster movie's all-star cast. Whedon confirmed in his recent comments that each new character will definitely have a major role in the upcoming Marvel film and they will not disappoint fans.

"I fiercely dislike the idea of just throwing in more people for the sake of doing that," said Whedon to Empire Online. "But last time I had all of Earth's Mightiest Heroes versus one British character actor, and I needed more conflict."

Whedon also tells Empire how he feels about making Ultron the biggest adversary in the movie.

"I'm having a blast with Ultron," said Whedon. "He's not a creature of logic - he's a robot who's genuinely disturbed. We're finding out what makes him menacing and at the same time endearing and funny and strange and unexpected, and everything a robot never is."

Ultron will be played by actor James Spader of "Boston Legal," "Pretty in Pink" and "The Blacklist" fame. In another interview, Whedon talked about Ultron's main goal in the new Avengers 2 sequel.

"I knew right away what I wanted to do with him," said Joss Whedon in an interview with Entertainment Weekly in August 2013.

"He's always trying to destroy the Avengers, god*** it, he's got a bee in his bonnet. He's not a happy guy, which means he's an interesting guy. He's got pain. And the way that manifests is not going to be standard robot stuff. So we'll take away some of those powers because at some point everybody becomes magic, and I already have someone (a new character, Scarlet Witch) who's a witch."

Whedon also talked about the new Marvel movie being filmed in the United Kingdom.

"The number of different looks and textures and moods we're getting from the British locations is stupid awesome", said Whedon to Empire Online. "Because this, palette-wise, is very different. I'm trying to make a different film. Because why would you make one movie twice? That seems weird."

Robert Downey Jr will return as Iron Man to lead the all-star cast against Ultron.

Samuel L. Jackson (Nick Fury), Chris Evans (Captain America), and Scarlett Johansson (Black Widow) are among the numerous actors set to reprise their roles when the smash hit returns to the big screen on May 1, 2015.