122408piven.jpgAs expected, actor Jeremy Piven's abrupt departure from the Broadway revival of David Mamet's Speed-the-Plow is costing the show's investors a mint; they had expected to finally break even just when Piven quit due to "mercury poisoning." The box office take dropped 33% in the wake of his withdrawal, and the money guys are livid. One producer tells the Post, "We were so close to recouping, and then this jerk screwed it up." Even Piven's former cast mate Raul Esparza is lashing out, telling the audience during curtain call last Sunday: "Today was the first time I really enjoyed playing this show. I hope you weren't expecting a big TV star." Meanwhile, actor Fisher Stevens has surfaced to defend Piven, testifying that he suffered from mercury poisoning earlier this year while eating fish four or five times a week during production of documentary The Cove, about the slaughter of mercury-loaded dolphins.