Complex sentence: After obtaining Victoria, Dexter has cruel experiments performed on her by his scientists in order to test her capabilities, after which he is infuriated to learn that 47 has captured his son Lenny and possibly killed him as retribution for taking the girl.
Split into simpler sentences: After obtaining Victoria, Dexter has cruel experiments performed on her by his scientists in order to test her capabilities. Some time later, he is informed that 47 had captured his son Lenny and possibly killed him as retribution for taking the girl.