When things go well, there's nothing as convenient as a trip on Metro, but a reluctant companion and a missing cellphone can cause a trip to derail.

A friend and I were riding back to Silver Spring on Metro. She normally does not take Metro and was not happy about it. While I extolled the virtues of Metro -- how easy it was to jump on the train in Dupont and relax in the seat as it whisked us back to the suburbs -- she frowned silently.

She wasn't buying it.

We missed the first train at the last second and spent fifteen minutes sitting on the cold bench on the platform waiting for the next one. The next train was packed. No relaxing as we rocketed across town squeezed against the back of the crowded train.

After Union Station, the crowd on our train started to thin out, and we found a seat together. Sharon was not pleased.

"We could have been back 30 minutes ago if we'd driven like I wanted to," she reminded me.

I pointed out the wonderful view to her, as the train climbed out onto the sunny elevated track. The CNN building outside Union Station, Rhode Island Avenue, the new condominiums in Takoma Park, and then finally Silver Spring.

The conductor warned us that Silver Spring would be the Last Stop. Our train was going out of service.

Everyone shuffled off the train. Sharon and I were among the last ones off, when I realized I'd left my cellphone on our seat.

"Sharon! My cellphone!" I yelped.

Sharon and I both jumped back on the train, as the conductor announced his last warning -- "Train out of service!" -- turning the lights out and snapping the doors shut, trapping Sharon and I inside the off-duty train.

Sharon and I ran to the door, but it was too late. Our former fellow passengers waiting on the platform for the next train continuing on to Glenmont, smiled in surprised amusement as they regarded Sharon and me under glass, pulling away from the station in the darkened train, our hands pressed against the window like prisoners.

As soon as the train left the station, heading for who-knows-where, Sharon and I whirled around and started screaming at each other.

"I told you we should have driven!" Sharon said as she jabbed her finger at me.

Worried that we were going to spend the night locked in an off-duty train car in some Metro lot, I started running up the length of the car to the conductor's box. The conductor was five cars up. Sharon continued to harangue me as we passed from car to car.

Luckily I noticed the intercom box at the front of one of the cars. I pressed the intercom call button and spoke clearly into the microphone.

"We are still on the train."

"What?" the conductor blurted.

"We are still on the train."

In a voice completely foreign to the crisp polite voice that had previously announced our upcoming stops, a strained, horse voice screamed out of the intercom at me. "You are not supposed to be on the train!"

The train came to a long, shuddering stop. I could hear doors slamming as the conductor made his way through the train from car to car. I cringed in anticipation as the door to our car was thrown open. The conductor gave us a long withering glare and stormed through our car to the engine car.

Our train pulled back into the Silver Spring Station. Sharon and I were still standing in front of the door. Our former fellow passengers were still standing on the platform waiting for the next Glenmont-bound train. They smiled when they saw us. The idiots had returned.

I got off the train with a red face.

Not Sharon, who snapped the last word: "Metro is not convenient!"

-- Adele Levine, Wheaton