Complex sentence: Luke was later kidnapped by Helena Cassadine but was held captive until September 30,2009, in which Lulu and Ethan rescue him and bring him and a sick Helena Cassadine back to Port Charles.
Split into simpler sentences: Luke was later kidnapped by Helena Cassadine and held captive until September 30,2009, when Lulu and Ethan rescue him. They bring Luke and a sick Helena Cassadine back to Port Charles.