The Lieutenant of Inishmore by Martin McDonagh

A farcical look at political violence as it's played out during the Troubles in Northern Ireland against the drab backdrop of a bare, rustic Irish cottage and unending boredom in an inhospitable environment in which a mutilated cat sets off a murderous cycle of revenge.
Wee Thomas was a friendly cat. He would always say hello to you were you to see him sitting on a wall. (Pause.) He won't be saying hello no more, God bless him. Not with that lump of a brain gone.
Who knocked Wee Thomas over on the lonely road on the island of Inishmore, and was it an accident? "Mad Padraig" will want to know when he gets back from a stint of torture and chip shop bombing in Northern Ireland: he loves that cat more than life itself.