The couple, who got engaged last November, kept their nuptials under wraps - so much so, that news of their wedding only broke after it happened!
Gossip Girl star Leighton, 27, and The O.C. actor Adam, 34, met in 2011 on the set of their movie The Oranges.
They have only been officially dating since February 2013 - and speculation is rife that they wed on their one-year anniversary, according to Us Weekly.
This is the first marriage for both. Leighton previously dated actor Aaron Himelstein, and Adam's exes include his O.C. co-star Rachel Bilson.
Congratulations to the happy couple!
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