Complex sentence: Seth and Regina have turned to crime after being unable to get work when the music halls closed down, and Seth has created an incredible world-wide protection racket based on Lucifer's ability to accurately predict impending deaths.
Split into simpler sentences: Seth and Regina have turned to crime after being unable to get work when the music halls closed down. Now Seth has created an incredible world-wide protection racket based on Lucifer's ability to accurately predict impending deaths.