Complex sentence: Poirot shows Power how the renaissance Pope used a hidden mechanism in the goblet to put the poison in the victim's drink and suggests that no good will come out of owning an object with such an evil history.
Split into simpler sentences: Poirot shows Power how during the Renaissance, the Pope used a hidden mechanism in the goblet to put the poison in the victim's drink. Poirot suggests that no good will come out of owning an object with such an evil history.