Take a trope character.

We’ll use The Distraught Mother for this example.

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She will weep, insist, fall to pieces. You see a distraught mother, a primal instinct takes over, nothing is important anymore except fixing this problem immediately.

Coincidentally, people who get what they want by means of manipulation know this.

So do screenwriters.

Trope characters create expectations. You can use those expectations to trick the reader, who will be very grateful when this particular Distraught Mother flags down a cop car, then steals it when the cop gets out, peeling rubber with the sirens on.

It will work even better if you set it up that the cop is responding to a call of critical importance.

It will work best if it turns out that the Distraught Mother is actually the perp he’s looking for and she drives the cop car right up to the helicopter she pilots away to safety.