Witherspoon joins untitled Brooks comedy

Remember James L. Brooks? He's the guy who directed "Spanglish," "Terms of Endearment" and "As Good as It Gets," and he hasn't helmed a flick in four years.

But now he's back, and according to Variety, he's working hard on an untitled Columbia Pictures comedy that will star Reese Witherspoon.

Plot details are strictly kept under wraps, and the only thing we know at this stage is that the film seems to be an "ensemble project that boasts at least three major characters."

Oh yeah, and the working title, according to the trade, is "How Do You Know?"

Witherspoon is currently onscreen in the box office hit "Four Christmases." She also voiced a character in DreamWorks Animation's upcoming animated adventure "Monsters vs. Aliens."