Assassin Cats: Book 1, The first hunt

A group of cats go undercover in a city to get rid of their boss's enemies, their boss helps them of course. He and his comrads kill the guys one by one until they are sure it is safe to return home, what they don't know is that the boss of the enemies is following them every step of the way.
This story is based on a world involved with cats instead of humans, these cats are the outcasts of the city whom they live. These cats fight for survival against a greater force but they must work together under their boss's orders in order to survive every day, they must either work together, go their seperate ways and die of being outnumbered, or work together but not in a group or they would be spotted and killed.