He was seated at the far end of my row, across the cabin, and there was nothing to notice for most of the flight. About an hour and a half before the flight ended, after the movies were through, I noticed him wandering around the near parts of the cabin, filming it with his video camera. I hid behind my chocolate chip cookie wrapper, not overly eager to be on someone's tapes under the circumstances. After a few minutes, a flight attendant noticed, and asked him to sit down.
A few minutes later, a flight attendant again noticed him doing the same thing, and asked him to sit down. He was obviously quite drunk and somewhat clumsy because of it. The flight staff had only given him two glasses of wine - he was drinking his own hard alcohol.
After a while longer, he started yelling from his seat, sporadically but loudly. "Free Tibet!" "Tibet is for Tibetans!" and the like. His stock phrases were limited but his silences no longer than five minutes at the outside. He wouldn't be quiet no matter how many times he was asked. He was given at least three warnings that the police would be meeting him when we landed if he didn't stay quiet. And he didn't, so they did.
If there's going to be a loud and obnoxious person on my flight, at least I had one who only started an hour and a half from the end, who was never violent, and stuck to yelling slogans.