Critic’s Choice: Spoiler alert! ‘Borrowed Time’ magic show will leave you astonished

“Borrowed Time,� a new magic act by Helder Guimarães, doesn’t quite defy description. Rather, it reminds its audience, with a conspiratorial wink, that description might spoil the fun for future audiences.

Those who attend this intimate, immersive performance, more an experience than a show, will be tempted to describe it. Merely knowing about it will give them the sense that they are hip and sophisticated, tapped into something vibrant and quasi-underground.

“Borrowed Time� takes place at a secret address, which is emailed to ticket holders on the day of the performance. The location looks unprepossessing, but like a speakeasy or an ancient tomb, it reveals trick doors and secret passages. One of its anterooms turns the audience into shameless treasure-seekers, ransacking drawers and cupboards for clues. It’s too thrilling not to recount in detail afterward -- except that not knowing the details is part of the thrill.

The well-meaning reviewer thus finds herself in a difficult position: eager to urge readers to buy tickets, but reluctant to explain why. Her position is especially precarious when illusion is so essential to a show’s charms.

The value and fragility of illusions are, in fact, one of Guimarães’ themes in “Borrowed Time.� When he was a child, he recalls at the start of his act, he told a younger cousin the truth about Santa Claus. His remorse over ruining this mystery impelled him to atone with other forms of enchantment: wordplay, tricks, a career in magic.

Guimarães is a close-up magician, expert at sleight of hand. His artistic medium is the deck of cards. In 2006, at 23, he won the title World Champion of Card Magic. He has performed for years at the Magic Castle, and with Derek DelGaudio as his costar and Neil Patrick Harris as his director, he created “Nothing to Hide,� which played at the Geffen Playhouse in 2012-13 and went on to an extended run off-Broadway. “Borrowed Time� is one-man show, written, directed and performed by Guimarães, with the support of a playful and proficient backstage team.

Card tricks may be inherently theatrical, but they require an intimate setting. The house at “Borrowed Time� is small, the guest list strictly limited to about 15. After the adventure of entering the performance space, visitors are seated two rows deep around a circular table where Guimarães will preside, on his feet, like a dealer in Vegas. Those in the front row, bellied up to the table, get to handle the cards. The back row, on elevated stools, peers over the front row’s heads. Everybody gets a good look at the action. Whether they can believe what they see is another matter.

Born and raised in Portugal, Guimarães speaks fluent English with a slight accent that makes his penchant for colloquialisms especially endearing: At big reveals, he tends to exclaim, “That is awesome!� He’s slight, trim in a sharp three-piece suit, and he wears glasses. He’s quick-witted and charming without coming off as slick. He seems, in fact, remarkably sincere and trustworthy for a man committed to deception.

If many of his tricks are variations on “Pick a card, any card,� they’re exceptionally clever, varied and astonishing. Guimarães has a natural gift for involving the audience, making them comfortable, even setting them up to be funny. The informal atmosphere, bare of special effects, makes it unnervingly likelier that the magician will show his hand — a possibility at once enthralling and distressing. So it’s even more impressive that he always gets the right card.

Guimarães is generous in suggesting that, given enough down time, any of us could master his skills. He even offers a means for intrepid adventurers to learn his secrets. But few of us took him up on it the night I was there. We preferred to remain amazed.

“Borrowed Time,� Secret location, Los Angeles. 8 p.m. Thursdays and Fridays; 5 and 8 p.m. Saturdays; 2, 5, and 8 p.m. Sundays. (See website for complete schedule.) Ends May 29. $85-$100. www.borrowedtime.la. Running time: 2 hours.

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