Complex sentence: Tony later releases Hayley, pushing her out of the door and causing her to fall over before setting fire to "Underworld", after dousing the building with petrol, determined that he and Carla would die together.
Split into simpler sentences: Tony later releases Hayley as well, pushing her out of the door and causing her to fall over. He then sets fire to "Underworld", after dousing the building with petrol, determined that both he and Carla would die together.