If you could tap into all your unused brain power, like Bradley Cooper does in 'Limitless,' maybe you could have predicted who would win the box office crown during this tricky weekend. Virtually no one predicted that Cooper's pharmaceutical thriller would come out on top, but in fact, 'Limitless' debuted at No. 1, beating the expected winner (last week's topper, 'Battle: Los Angeles') and two other new releases.

After 'Battle: Los Angeles' (and perhaps 'Rango'), the three newcomers ('Limitless,' 'The Lincoln Lawyer,' and 'Paul') were expected to compete in a tight race, each opening with 2,700–2,800 playdates and projected sales of $11 to $16 million. But 'Limitless' pulled ahead of the others with an estimated opening of $19.0 million, thanks largely to positive reviews and broad appeal. (Distributor Relativity said 60 percent of the audience was over 25 and that viewers were about evenly split between men and women.) Sci-fi genre competition from fellow newcomer 'Paul' and holdovers 'Battle: Los Angeles' and 'The Adjustment Bureau' didn't seem to have much impact.