Complex sentence: The group plan to find Polo's ships and reputed treasure for themselves and cheat Flynn's client but unbeknownst to Flynn, Chloe convinces Nate, her ex-lover, to leave with her once they get their shares.
Split into simpler sentences: The group plans to find Polo's ships and reputed treasure for themselves and cheat Flynn's client. Unbeknownst to Flynn, Chloe convinces Nate, her ex-lover, to leave with her once they get their shares.