Mac and Lauren is the brainchild of Lisa Dennis, the wife of Team McLaren Mercedes CEO Ron Dennis. She has created a fantasy world of Grand Prix racing action where the cars are the stars! The cars are caged in on the long flight to Australia. Harry is pleased when Bruno and Maddy want to be his new best friends. But is friendship all they're after? Soon Harry's being hassled to play a dangerous joke, and it's computerised chaos on the track. As Mac struggles to help his friends, Lauren must burn down to scary Race Control to set things right -but she's helped by some special Aussie wildlife...