Cocker spaniel Diesel is a hearing dog for his teenage owner, Rayane, who is deaf. This means Rayane doesn't hear everything. Diesel's superears are trained to alert Rayane to important sounds he might miss. Diesel is Rayane's ears! Diesel has to ignore lots of noises on the way to the pet shop. He uses his superhearing to zoom in on the important sounds like the pet shop door bell. Diesel helps Rayane find the pet food aisle, where he chooses his pet food and a new toy, while being careful to choose one without a squeaker. Squeakers are for training time, not playtime. But then there's an emergency at the cafe when the smoke alarm goes off, and the cafe has to be evacuated. Diesel must use all his training – and his superears - to help guide Rayane and Mum to safety.