Sequels
In Hunters of Dune, the passengers of the no-ship Ithaca discover that the Handlers are indeed actually Face Dancers from The Scattering, in league with Daniel and Marty (who are not). It is also revealed that these new Face Dancers (apparently undetectable by even Bene Gesserit means) have infiltrated governments and other powers across the Old Empire in their plan to take over the universe. Murbella and the Bene Gesserit stumble upon this when they discover that the leader of the Honored Matres on the planet Tleilax and her inner circle are in fact Face Dancer duplicates.
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