Complex sentence: Meanwhile, Reggie falls in love with Alex, but when she learns from Bartholomew that Carson Dyle had no brother, Alex says that he is actually Adam Canfield, an unabashed professional thief.
Split into simpler sentences: Meanwhile, Reggie falls in love with Alex, but then she learns from Bartholomew that Carson Dyle had no brother. Alex now says he is actually Adam Canfield, an unabashed professional thief.