Here comes the bride — and she looks stunned.

Brooklyn bride Sara Valencia got the surprise of her life on her wedding day thanks to her husband and a little help from TV host Cat Deeley.

Vince Eaton, 29, tricked his bride-to-be into thinking they were being filmed for a show about a frugal wedding with a $10,000 budget. In reality, he and TLC were working behind the scenes to give her the lavish reception of her dreams.

Her shocked reaction is revealed in “Secret Wedding,” a special airing Friday at 10 p.m. on the cable network.

“It’s really hard to lie to a person you’re going to marry,” says Vince. But since the fib was in the name of love, he made an exception.

The Park Slope couple — who now share the combined last name of Eaton-Valencia and both work for nonprofits in Manhattan — first met at a Keen Company theater fund-raiser in Hell’s Kitchen two years ago.

Once they became engaged, they responded to a casting call to appear on a “budget wedding show.” Soon after, TLC told Vince the real premise of the show, and he agreed to keep the extravagant plans a secret from Sara.

At the time, Sara was working as an intern earning just $7.50 an hour and Vince was between jobs. The couple was originally planning to stick to their shoestring budget of $10K. Vince’s dad had sold his antique stamp collection to supply the cash.

Sara, 26, had always envisioned a rustic barn wedding but couldn’t afford it and was willing to settle for less.

“Rustic is romantic for me,” Sara says. “I wanted it to be whimsical.”

On the morning of the wedding in August, show host Deeley arrived at the venue — a white barn at the Hallockville Museum Farm in Riverhead, Long Island — surprising her with a stunning sweetheart wedding gown. It replaced a plain online purchase Sara had reluctantly settled for.

“It was magical,” gushed the bride.

A designer gown wasn’t the only upgrade made that day. Sara thought she was going to walk down the aisle with a potted plant for a bouquet, but she instead held an extravagant arrangement.

Her homemade canapés were replaced by seafood paella, cupcakes gave way to a custom three-tier wedding cake, and a salsa band stepped in for the DJ.

“It was complete and utter shock,” Sara tells The News.

But before the boost from TLC, the low-maintenance bride was wedding-planning DIY-style.

“I had to scour Craigslist like a madwoman!” she says of buying a chainsaw to make wooden center pieces and spray paint for decorations she learned to craft on Pinterest.

Sara planned to do her own hair and makeup and was even going to play photographer with a digital camera. But TLC hired a glam squad complete with an airbrush makeup artist, a hair stylist to curl her locks, and a professional photographer to capture the fairy tale event.

But the bride’s biggest thrill was the ride of her life in a DeLorean — the same model car that travels back in time in the couple’s favorite movie, “Back to the Future.”

“It was hard enough to incorporate our geek culture,” says Vince, who also surprised Sara with a superhero photo booth complete with “Batman” masks and light sabers, a table of board games like Jenga and Bananagrams, and a custom zombie wedding cake from City Cakes in Chelsea.

“We’re definitely going to be prepared for the zombie apocalypse,” jokes Sara.

The gamer couple exchanged vows in High Elvish language, reenacting a scene from “The Lord of the Rings.”

“One ring to rule them all!” says Sara.

“Well, now it’s two rings.”