Liam NeesonWinning what was quite the slow past few days at the box office, "Unknown" edged out "I Am Number Four" for the top spot over the President's Day weekend.
The Liam Neeson/Olivia Wilde thriller garnered the pole position with an estimated $21.7 million in earnings.Having grabbed up the most money on Friday (February 18), Dianna Agron and Alex Pettyfer's "I Am Number Four" slipped a bit while ending up in second with an approximate three-day total on $19.5 million.
Rounding out the top five at the box office were "Gnomeo & Juliet 3D" ($19.4 million), "Just Go With It" ($18.2 million) and "Big Mommas: Like Father, Like Son" ($17 million).
