According to Variety, Gary Oldman has signed to portray attorney Melvin Belli in Zodiac, Paramount and Warner Bros.' serial killer thriller to be directed by David Fincher.

Oldman, currently in Batman Begins, will star alongside Mark Ruffalo, Robert Downey Jr., Jake Gyllenhaal and Anthony Edwards. Production's slated to begin in September, with Jamie Vanderbilt adapting from Robert Graysmith's Zodiac and 2002 sequel "Zodiac Unmasked: The Identity of America's Most Elusive Serial Killer Revealed."

Belli, the San Francisco-based "King of Torts," received a letter from the Zodiac in 1969 in which the killer wished the attorney a Merry Christmas and said he hoped to retain enough self-control not to claim a ninth and 10th victim.

Warner Bros. is the lead studio on Zodiac and will distribute internationally while Par handles domestic distribution.