Complex sentence: The saboteurs are eventually revealed to be Thufir Hawat and the Rabbi; having been replaced with Face Dancers back on the planet of the Handlers, the two have been wreaking havoc since.
Split into simpler sentences: The saboteurs are eventually revealed to be Thufir Hawat and the Rabbi. Having been replaced with Face Dancers back on the planet of the Handlers, the two have been wreaking havoc since.