How is The suspense created in the film you watched in class?

The film I watched in class, 'What lies Beneath', was what the task was based on to list examples of how suspense was created.

The first example was Norman appearing at the back of the car, this was scene was an example of the false plateau. False plateau is when you think something is going to happen but it does not happen.

As an example, the lady sees another woman crying then walks up to the hole and sees the garden moving.

Also, when she jumps into the lake and finds the box at the bed of the lake.