Ok for example, I start by saying,"Unfortunately there was a giant evil pillow on the the loose; then the next person would say...Fortunately I had a knife with me and stabbed a hole in it"
Ok lets start. Unfortunately I was being chased by an elephant...
Nitroglycerin is a chemical used in the manufacture of dynamite (pretty much what makes dynamite explosive) and some sort of medical treatment for heart conditions.
So yeah, it'll likely explode due to the shock from the impact with the people who landed on the vials of nitroglycerin.
Unfortunately, the resulting explosion opened up a deep hole in the ground which swallows everyone.