The Joker hit the end of the alley with time to spare, yanking an unsuspecting cab driver out of the half-open door of his cab. "Tyanks for opening the door. What a gentleman." He slammed his foot down on the gas cackling as the car sped into traffic and several other cars honked and swerved to avoid him. "I FORGOT YOUR TIP!" came the scream out the car window as it sped off. A few seconds later, the grenade stolen from the fallen henchman clattered down the street behind the car.
The explosion overturned a car and sent more cars swerving to avoid the chaos. Meanwhile, The Joker was halfway down the street, his eyes scanning for pedestrians that made the mistake of trying to cross the street, the car hurtling down the street without falter. He swerved for no one, several times driving in the wrong lane on purpose to force others to over correct and crash. Pedestrians dove to clear out of the way, and one was clipped while trying to make it to the curb.
Despite the apparent randomness of his bobbing and weaving technique, The Joker did have a destination. He flew around corners, driving deeper into the city, and listening all the time for the high-powered whine that would bring the Bat up behind him.