A cloak of invisibility is a very expensive but excellent holiday gift for almost anyone — if you can find one to buy. As soon as they are put out they typically just disappear off store shelves.

It’s a very handy thing to have about the house. You can use it for hiding Christmas gifts or for screening a messy project table just before guests arrive. You can make yourself disappear when the spouse comes to find you with a “to-do” list. Also it’s great to be able to hide in plain sight when in-laws or annoying acquaintances pop in.

My only experience with the cloak is in the theater. It’s not really firsthand experience but it’s the only explanation that fits the circumstances I have witnessed.

The cloak will allow people to walk onto or off a set without the audience seeing them. It can make set pieces disappear between acts or hide lighting instruments and stands that need to be set up center stage to satisfy a director’s whims. Even costume changes can take place on stage. Almost all the magic acts I have seen obviously employ a cloak to pull off at least half of their tricks.

In case you are not familiar with a cloak of invisibility, it looks to be made from a fabric which, when viewed from one side, appears to be a thin, gauzy material that holds in place all of the quantum invisibility technology but, when viewed from the other side, is completely transparent and, for all practical purposes, invisible.

Technically, the cloak does not make you invisible; it’s the cloak itself that’s invisible. If two people hold up the cloak, all you see is what’s behind the cloak and two idiots holding up nothing. The trick is to surround something with the cloak to essentially make whatever is surrounded disappear to the casual viewer. It’s very much like surrounding your brain with a tin foil hat so that people on the outside can’t probe what is going on inside.

I recently discussed recurring theatrical problems with Paul Hodgson, a compelling actor/producer/director who somewhere in life took a turn and, to our benefit, wound up living near my home in Maine instead of New York or London. We agreed that there are few problems on a theatrical set that can’t be solved with a cloak of invisibility.

Paul was upset because he could not find a cloak to buy for his last production. I suggested that he rent one from a theatrical supply house but he just chuckled. “You have to buy them,” he said. “Nobody rents them anymore as people have been charged astronomically high prices after being accused of not returning them to the rental house.”

“I did bring it back and set it right there on your counter.”

“Well, I never saw it. I’ll have to charge you full price.”

“Of course you didn’t see it, it’s invisible.”

“If you want to come back here and show me where it is, be my guest.”

“If you moved it, how am I supposed to find it?”

“So do you want to put that on a credit card or will you need to get a home equity loan to pay for it?”

The cloaks do come with some inherent drawbacks. A major problem is that they are extremely hard to find if folded the wrong way and misplaced. Even dropping it can be a problem. Some people have gone to pinning those little electronic locator tiles inside but you still have to be diligent as your tracking device may tell you that the cloak is right there in front of your nose and you still won’t be able to see it.

Sadly, new cloaks are no longer being fabricated so their cost has skyrocketed. The group that was producing them was rounded up for deportation earlier this year after suspicions arose that they were illegal aliens. Aliens indeed. They took their alien technology with them and just disappeared.

As far as acquiring a cloak of invisibility: if you “see” one, buy it. They are getting very scarce. You might ask any well-connected magician, theater friend or CIA agent you may know for a lead. It’s rumored that a large cache of cloaks was shipped to election officials in Florida but if you buy them there, you may find a bundle of ballots inside the cloak that could make things awkward.

Happy gift hunting.