Question: How would you get on the roof of a moving subway? We don't see it in the movie (Jack looks up and starts to climb - cut - Jack is on the roof.... Howard cries 'I'm coming for you Jack and runs - cut - Howard is behind Jack on the roof. after the fight when Howard 'lost his head' - cut - Jack is inside the subway again...).
Toolio
3rd Sep 2004
Answer: Ventilation shafts or roof panels.
Toolio