Suspense is created in the Step Father through the use of the following;
NORMALITY: This is established at the start of the film as the Character (David) Showered, shaves, drinks coffee, eats toast, puts on the radio but the action become subverted when we see dead bodies in the living room.
FALSE PLATEAU: Suspense was created in the film Step Father as events was unfolding. An example was when the "cat lady" was in her house and a cat jumps out. We were relieved that it was not a killer but then, He appears!!!
BOMB THEORY: This also a significant aspect in how suspense was created. For example when David meets the women in the shops, we (the audience) know that he is a serial killer but the characters do not know. David is the bomb.