A ride on the 146 bus is usually quiet. The chirp of cell phones on the 136 can make you crazy, but the sound of the 146 is the rustle of tissue paper in expensive shopping bags. But the ride home after the recent Saturday-night Lyric Opera concert in the park proved that things can change, and change quickly. On State Street at Madison, dozens of late-middle-aged music lovers got on, hauling lawn chairs and quilts and giant picnic hampers, all of them buzzing with postconcert excitement. People saw their friends and blew air kisses up and down the aisle. Everyone agreed: the music was gorgeous. Renee Fleming is a treasure. The weather was perfect. The 146 had became a party bus, without the drinks.

When the bus turned onto Michigan things got ugly. The bus was packed. At one stop, a rumpled-looking man allowed a group of elderly concertgoers to board first, then couldn’t get on himself. He was about 45 and very sweaty. He asked if people could move back so he could squeeze in, but no one budged, so he ran to the back door and stepped up. A woman blocked his way, shouting, “Driver! Stop the bus! This man didn’t pay!” His clothes set him apart from everyone around him, but the woman’s manicured hand pointed him out just in case. He said he’d be glad to pay, but she kept him in the stairwell. As a result, the door wouldn’t close, and when he tried to force it, it jammed.

The driver announced, “We can’t leave till the door’s closed.” The guy jiggled it, then called to the driver, “I can’t close it. What should I do?” A collective sigh of annoyance swept over the bus. A redheaded woman in a lavender sweater yelled, “So get off the bus, shithead.” Suddenly, the bus erupted with obscenities directed at the hapless man. The door still wouldn’t close–or open. Finally, the driver himself came back and fixed the door, but as soon as he did, the lights went out and the engine died.

Everyone groaned. Then the silence was broken by a woman behind me yelling, “Nice going, asshole.” The guy just stood there, stunned. An elderly man in a golf hat stood up and bellowed, “Get off, you prick!”

Finally, with the hostility in the back building, he exited the rear door and dashed toward the front of the bus, only to have the driver shut the door in his face. The crowd jeered and laughed at the guy, and as we pulled away from the curb, the whole bus erupted in cheers. On the drive, the pastel-clad, lawn-chair-toting defenders of Civilization glowed with righteous victory. They had successfully defended the 146 against a seething horde of aggressive poor people with bad haircuts and cheap clothes. Or at least, that was how one woman saw it. To no one in particular, she said, “People like that shouldn’t be allowed to get by with that kind of behavior. Just one person can spoil the evening for everyone else.” By the time we got to Belmont, they were talking about music again. A few minutes later, it was quiet on the 146, the only sound the traffic on the Outer Drive.