What is a good plot 4 a play or movie?

i luv 2 write but i have writers block!! umm i want it 2 be scary but i dont noe how 2 start it! i want i creepy and scary and ummmm mysterious. but i want it LIKE REALLY SCARY!! soooo plz help me with this cause writing is the one way i express myself but i luv scary stories. i could be a play or movie! oooohh yea and also could u give me soome characters names personalities and if they will be the killer! you guys roq cause i noe u will get something good!! OOOHH also need A TITLE!! evn if u can not think of a story give me characters or title!! thankz <3