Insane Cat

I am the proud owner of two cats, Sam & Twitch (10 points if you know the reference). Normally, these are incredibly docile, gentle, friendly cats. They are indoor cats, so their fur remains white, their toe-pads pink and soft and my vaccination bills small.
In our neighborhood, there is a certain smokey-grey cat that is allowed outdoors. This cat takes great delight in hanging out right outside our windows. When this happens, and Sam is aware, he goes absolutely apeshit. He meowls, he growls, he moans, he throws himself bodily at the windows, and if they’re in the way, the blinds. He scratches, he hisses; he loses all recognition abilities and attacks the nearest living thing. This has included plants and myself, but more often than not, the recipient is Twitch, perahps drawn over to investigate alongside his brother this thing outside. Twitch, while clearly also disturbed by this other cat, is not agressive, but will watch the other cat warily, an air of prestige about himself. In other words, he maintains his dignity and his superior airs.
But not Sam. When Sam attacks Twitch like this, it is an all-out catfight. All the noises, screetches, scratches, bites that go along with it. Fortunately, up to now, the most serious injuries have been some nasty looking scratches on their noses (disturbingly close to their eyes for my liking), and nicks here and there elsewhere. But I’ve always been around to break them up, separating them with a spray-bottle then locking one of them in a room until they’re both calm, and start to clean themselves. But I worry what might happen if there is no human to intervene in these fights, I must say. I would hope that recognition abilities, or tiredness would kick in before anything life-threatening occurs, but I really don’t know right now.

Last night, I crawled into bed around 1:00. At 3:30, a fight broke out. I seperated them. By 4:30 I was finally just falling asleep when once again Sam lost it. 5:30, same thing. Each time, it was the damned cat outside. The last time, I opened the window and I threw a bucket of water at the other cat, fully drenching it (it was as unconcerned about me as it is about our cats). Hopefully, it will remember that and not come by for a while. Hopefully, it’s owner won’t be too upset about a drenched cat.