Sometimes when I design scenarios, I realize that my mental image of the adventure is only exciting because it takes place at night. When the players actually play through the adventure, they might foil my plans by simply deciding to investigate the haunted forest during daylight hours.

In horror movies, they always find a reason for the scary parts to take place at night (even if that reason is just sheer stupidity). In a tabletop RPG where the PCs have free will, things aren't quite as easy.

**When an adventure needs to be set at nighttime in order to be dramatic, how can I make sure that it actually takes place at night?**