Your car will always start immediately unless you are being chased by a maniacal killer or a monster of genetic creation. Crazed maniacs have super-human strength. Haunted houses are never locked. Murders will always be accompanied by sinister music. Rich people are unhappy.
Thunderstorms spontaneously create murders.
When someone is dead or dying, there will be a trickle of blood from the corner of their mouth. Christmas Eve and Halloween night last for three of four days. Midnight happens more than once in a monster movie. To kill a vampire, you must set out 5 minutes before sunset. Nobody ever realizes until the end of a monster movie, that everyone that went into the dark cellar never came out.