While Marvel's Phase Two slate is just getting started, with this summer's release of Iron Man 3 and the upcoming Thor: The Dark World, Marvel Studios are currently focusing on casting their first Phase Three movie, Ant-Man. Inside sources claim that Joseph Gordon-Levitt and Paul Rudd are the top two candidates for the title role, although no offers have been made yet.

The unidentified sources reveal that there is the possibility that another actor may emerge with the coveted role but, as of now, Joseph Gordon-Levitt and Paul Rudd are the front runners. Both actors are expected to meet with Marvel executives and director Edgar Wright one more time before a final decision is made.

Ant-Man is based on the Marvel comic book series that follows Dr. Hank Pym, who invented a substance that allows him to be shrunk down to an ant's size. It was rumored that the director is focusing on Hank Pym's later years, adding criminal Scott Lang, who steal's Pym's technology and becomes another Ant-Man. There is the possibility that both actors may be cast as these different Ant-Men, although that scenario seems unlikely.

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Earlier this month, the director released a pre-production photo that revealed an unidentified actor in a motion-capture suit. There were also rumors this summer that Simon Pegg was cast as Ant-Man, although the actor shot down those reports just a few days later. It's also worth noting that Joseph Gordon-Levitt was a contender to play Star-Lord in Guardians of the Galaxy, a role which ultimately went to Chris Pratt.

Edgar Wright is directing from a screenplay he co-wrote with Joe Cornish (Attack the Block), based on the Marvel Comics character created by Stan Lee and Jack Kirby. No story details have been confirmed at this time, but stay tuned for more developments regarding this highly-anticipated project.

Joseph Gordon-Levitt most recently starred in and made his directorial debut with Don Jon, and he will next be seen in Sin City: A Dame to Kill For. Paul Rudd briefly appeared in the summer comedy This Is the End, and he will next be seen reprising his role as Brian Fantana in Anchorman 2: The Legend Continues.