Angry, Angry Cat

My cat saw another cat outside and started freaking out. The first time she did this she woke us up and I sent Cliff downstairs convinced she was being hacked to death by some crazy cat murderer.

There is a cat that looks very much like her that will sit outside the living room window. She screams when she sees it. I mean it - its a scream. Today she was banging her head against the window in an effort to attack. I'm yelling at the other cat to get away but he ignores me. Finally I open the door to yell at it and he still wont' move. My cat and I are now outside. I'm in my under things. Finally the cat takes off. But wait - was it my cat that took off? Back into the house to put something a little more decent on. Thankfully I ended up with the right cat - but I admit I wasn't sure at first - especially when she started purring when I picked her up. She does not purr for me or sit on my lap. Only Cliff. I guess with him gone for a few days she figured she had to take what she could get!