You could also leave one or more of the main characters in a life-threatening situation at the end of a chapter
i.e. leave them unconscious on the floor while a building or house is on fire around them.
Just my two cents worth.
Okay, folks! *points to the left* The line to shoot Brian forms to the left. *points to the right* The line to shoot Dr. & Mrs. Carrswold forms to the right. Take your pick.