One day, during my retirement, if there is still Social Security or whatever, I plan to write a collection of short stories called “Places I Have Lost My Son.” I lost him once in a state park, where, during a verdant and filthy family hike, he ambled ahead 10, then 20, then 500 yards, past a vigorous series of intersections and switchbacks. (We found him at the ranger station, making plans for what to do with his months-long iPhone ban.) I lost him once from his own bedroom when, at age 4, he let himself outside at 1:30 a.m. in a half-sleeping dream state, in search of the Polar Express. (We found him 20 minutes later a quarter-mile down the road, where he’d been discovered by two teenagers named Kevin and Brendan who were most assuredly not Tom Hanks.)

I’ve had to find him in zoos and museums, malls and airports, when something catches his imagination and instinct compels him to follow it. In my son’s brain, imagination is not some zingy, lively Peter Pan-type. It’s a 500-pound sumo wrestler who lumbers in and shoves aside all of the functions used for mindfulness and consciousness and “remembering to look behind him to see WHERE HIS DAD IS.” It’s both delightful, as there is no greater gift than childhood creativity, and god-awful terrifying, as there are few worse feelings than having to ask the nice security guards whether they have seen a 12-year-old in a blue hoodie. Twice.

Which brings me to how we totally lost him on the London subway.

First, let me spoil the ending: The little space cadet is fine. For all of his gifts for sporadically vanishing into thin air, he is a resourceful guy who generally (KNOCKS ON ALL THE WOOD, THEN FINDS MORE WOOD ON WHICH TO CONTINUE KNOCKING) knows how to extract himself from such situations. In the state park, he asked for directions from a hiking family, figuring, he told us later, that they would be helpful because they had two kids. In the local children’s museum, he usually just hangs out by the Rube Goldberg machine.

The subway, though, was just a case of bad timing. We were on an inaugural overseas vacation with our 12- and 5-year-olds. It was late in the day, and it had been hours since we’d had any fish and/or chips, and we were sprinting through Piccadilly or Upminster or Paddington or Tooting or whatever station we were in (Tube stations are so British-sounding I initially thought they were kidding, especially Cockfosters). And I think we must have just missed the door-closing bell, because as we half-jogged into the station, my son boarded the train, my wife (who was right behind him) glanced back to make sure I was following and the doors slid shut, trapping my son and his wide-open eyes inside, then rocketing him off into a tunnel. The look on his face will be pretty much burned into my nightmares forever (which is good, as it’ll block out some of the clowns).

Now, several thoughts careen through your mind when an unfamiliar train speeds your child into darkness, alone. Some of them are stupid ideas (in case this ever comes up, no, you can’t pry open train doors with your fingers), and some of them are exceedingly stupid ideas, such as looking for some sort of external brake. Most of them are just curse words you shout in a crowd of nice London commuters.

And then there’s the matter of formulating a plan, which is hard to do when you are frantically running around all eight feet of a tube-station platform looking for one of those British police in the giant blue hats with the pointy things on top. (They still have those, right? Do they still have those? Because that’s pretty much what I was looking for, or a beefeater, or Doctor Who, or Liam Gallagher, look I don’t know a lot about the British law enforcement system.)

Luckily, I found that the best thing to do in this scenario was to consult my wife, who decided to wait for the next train, board the same car my son did and collect him at the next station, figuring he’d get off there and wait for us. Which is what he did. (The next train arrived in like 40 seconds. FYI, London’s trains are 8,000 percent more efficient than New York’s.) He was out of pocket for maybe 90 seconds, which makes that headline total click-bait, sorry.

But he did what he should have: He tried to text us, then got off at the next stop and waited. Had we not shown up, he said, he would have found the police. There is a lot of imagination in his brain, thoughts and impulses crackling like crossed wires. But I’m heartened to see there is also a solid foundation of common sense, the idea that if a situation goes to pieces, the best thing you can do is keep calm and carry on.

You can find Jeff Vrabel, a writer, @jeffvrabel and on jeffvrabel.com.

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