Complex sentence: Shortly after venturing out into the countryside, Cobretti becoming romantically involved with the witness, one of the Order's leaders (who was also a police officer) reveals the location of Cobretti, the witness, and Cobretti's partner.
Split into simpler sentences: Shortly after venturing out into the countryside, Cobretti becomes romantically involved with the witness. One of the Order's leaders (who was also a police officer) then reveals the location of Cobretti, the witness, and Cobretti's partner.