Complex sentence: A tape informs the victims that antidotes are hidden throughout the house, one of which is in the room's safe; the combination is "in the back of their minds" with the order found "over the rainbow".
Split into simpler sentences: A tape informs the victims that antidotes are hidden throughout the house. One of which is in the room's safe, and the combination is "in the back of their minds" with the order found "over the rainbow".