A small, mostly curious crowd formed around the men as they lingered by the auditorium wall, accusing Khan of subverting British law, without ever explaining how. When a reporter asked under what authority they planned to arrest the mayor, one of the Pendragons cited the Magna Carta.
Police had still not arrived after 10 minutes or so. One of the Pendragons walked up to Khan's table and showed him an American flag, which he was holding backward.
"Mr. Khan," the man said, "there's millions of British people supporting Donald Trump."
The audience booed especially loudly at this. "Good one!" Russell cheered.
"Please sit down, sir," Green said. So the man walked back to Russell, holding his flag up to the news cameras, still holding it the wrong way.
Green eventually began to lose patience with the men. "I am not having you dictate the way this meeting is conducted," she said. Eventually, Sky News reported, Khan began to read a newspaper.
After a quarter-hour standoff, Russell pointed his cellphone at his own face and happily announced to his Facebook viewers: "There's an inspector outside we have to speak to now over these charges against Sadiq Khan."
But when the constable walked into the room, he simply told Russell: "You'll have to leave now."
Russell handed the officer a sheet of paper outlining his complaints. One of them cited the Coronation Oath Act of 1688. The officer looked at it. "We are going to investigate," he promised, not entirely convincingly.
"Well, the grounds for the arrest are all there," Russell said.
"We don't do citizen's arrests," the officer explained. "We do lawful arrests."
Russell finally followed the constable outside, to much applause from the crowd. One of his compatriots waved a water bottle aloft as they left.
Khan stood up and resumed his speech. "It's a pleasure to be here," he said, "even though we were distracted by the actions of what some would call very stable geniuses."
The crowd laughed at this. Outside in the lobby, his gallows still empty, Russell continued to argue with police. He also asked for a refund on his ticket.