在香城 (Aroma City) 這個繁忙的都市中，人類為生活奔波，完全沒發現周遭的動物們也有牠們的生活。
Aroma City is a bustling Chinese metropolis, full of busy humans going about their busy lives. Humans are so busy, in fact, they have absolutely no idea that the animals who walk, fly and swim among them, have busy, hectic, stressful lives of their own.
In the secret animal world of Aroma City animals, there is well-defined hierarchy. There are the gang lords that jealously guard their territories; there are the normal animals who are just trying to get along; and there is Madam Pearl. When good, law-abiding animals have a problem they call on Madam Pearl. If Madam Pearl is interested in their case, she deploys Aroma 5, her team of ace acrobatic detectives to solve the case… but only for a price!