Complex sentence: Lydia overhears the conversation and sabotages Zoë's parachute before the jump in an attempt to kill her, however the parachutes are mixed up, which makes Lydia panic.
Split into simpler sentences: Lydia overhears the conversation and sabotages Zoe's parachute before the jump in an attempt to kill her. However, the parachutes are mixed up, which makes Lydia panic.