I had a teacher once who said to add conflict, give characters a countdown/ clock .
So here's the thing: Your characters have a problem to solve- but they have a limited amount of time to do it. For example, by midnight, by daybreak, within an hour, etc.
Write a scene of part of this. You can show the planning, the climax. or how they're dealing with the gradually decreasing time. Are they starting to panic or calm?