She showed a scene from Medium in which a mother and daughter are waiting in a doctor's office. The daughter is called in and tells her mother she doesn't need to come with her, she'll be fine. Too much time passes, the mother asks what's taking so long, the nurse discovers the door is locked. Upon finding someone with a key, they open the door and discover the room covered with blood. The girl is dead, covered with a sheet. A large dish filled with intestines is sitting where her right leg should be. The doctor is sitting in the far corner of the room, reciting his Hippocratic Oath. The door pulls further into the room, and a man in a dark suit tells the nurses and mother to wait outside, he'll be right with them--in a cockneyish accent. The main character (the medium) wakes up in a start.
We discussed different moments in the scene that increased suspense. Different people first picked up on the tension at different points--"I'll be fine, Mom"--the time was after five o'clock at a doctor's office--when the mother and nurse passed a vase of red orchids--when they discovered the door was locked. I noticed that the scene really wasn't out of the cliche until the moment the man in the dark suit jerked the door open. We talked about the power in reversing/undermining cliches.
CV: Withholding information can sometimes backfire. Also, remember the POV of a victim isn't usually that interesting. A piece of meat. I like to use implication to form a kind of creeping dread. Then there's the Wash Effect (having a beloved character die to show the reader/viewer that anything might happen). I like to introduce a second problem before I resolve the first. Escalate problems.
Something to be wary of is the idiot plot. Like The Blair Witch Project. I was telling a friend of mine about the movie. He said, "They're in the woods?" "Yeah." "There's a stream?" "Yeah." "Why didn't they follow the stream out of the woods?" Punishing your characters for just being stupid is a letdown. Aliens was much scarier. A movie about these marines, they were all ready, at the top of their game, and it still wasn't enough.
Pacing is what you are telling the reader, when you are telling the reader, so they can figure out what's going on.
PPW: How much is too much? (Increasing plot problems.)
CV: The point where you say, "Can they still get out of it" and it's not believable anymore, that's too far. If it's in service of the plot, I say go for it. Like Lois McMaster Bujold. All these terrible things happen to one of her characters...but there's always room to grow at the end of each novel.