“Limitless” rockets to No. 1, and Bradley Cooper’s POV rockets in “secret” visual effects sequence.

'You talking to me?"

Not long after Bradley Cooper ingests that little clear pill in the #1 box office thriller Limitless, the camera starts zooming around New York, whooshing through cab windows and rocketing up bike lanes. It’s an exhilarating mix of ace cinematography, editing and visual effects. “How do you show how he’s feeling, and what his sense of the world is, and how he processes information?” says Neil Burger, discussing Cooper’s turbo-IQed character and the challenges that sequence presented. “I was extrapolating ideas about how he would think about mirrored parts of a larger hole and I was thinking about fractals…. It’s almost like an Escher-like zoom, where you go in and you think you’ve gotten to the small part but then you realize that it’s just opening into a new world which is larger. And I wanted to do something like that, but in the context of this teeming city. I wanted to do it outside and have this infinity zoom -- to represent his brain and how he moves through space and time.”

Got all that? Burger says that exactly how they achieved that sensation onscreen – a dizzying feat done in collaboration with a company called Look Effects -- “is kind of a secret.”

What’s not a secret is that Burger -- whose work includes the Iraq-vets-come-home road pic, The Lucky Ones, and the rewardingly tricky Edward Norton/Paul Giamatti/Jessica Biel period piece, The Illusionist – was thrilled to be working with Robert De Niro, who plays a billionaire powerbroker opposite Cooper’s pill-popping savant in Limitless.

“Look, he’s my favorite film actor, and certainly one of the greatest film actors ever,” says Burger, who admits to some surprise at how easy De Niro was to work with.  “Going in, I didn’t know. Is he going to be ornery, or unwilling to do something, or resistant somehow? And he wasn’t. He actually asked for direction, wanted direction, took direction. … It was just really easy. And I know Bradley felt that way, too…. There’s a reason De Niro is who he is. Somehow, his emotions and what he’s thinking are transmitted so easily through how he sees the world.

“Look, I’m sure he’s had phases in his career when he’s been less easy… but I do know we must have caught him at a great time, because he was pretty delightful to work with.”