After three years and 246 episodes as one of television's highest-rated prime-time game shows, no one had ever won the million-dollar grand prize on NBC's "Deal or No Deal."

Until now.

The first contestant to beat the game's astronomical odds is a stay-at-home mom from Sandy.

Her name is Jessica Robinson, a 27-year-old housewife and mother of one who is expecting a second child at the end of this month. And she not only won the grand prize but also used the show to announce to her family - and the nation - that her next baby will be a boy.

"We went into the show thinking I wasn't going to win a million. I just had a plan, and I was going to stick to my plan," she told The Salt Lake Tribune before the episode aired Monday night.

That plan was simple: She would pick the case to keep that she thought contained the million dollars - case No. 4 (based on the fact there will be four in her family). Then as she progressed through the game opening the rest of the 25 cases one by one, she would save cases No. 26 and No. 14 as her last two, thinking they had the next two highest money amounts. (Her family helped her choose those case numbers).

Amazingly, she was right. The case she picked was one of five in play that had a million dollars, while case No. 26 had $200,000, and No. 14 had $100,000.

Robinson, who was nearly 30 weeks pregnant when they filmed the episode in Los Angeles on July 9, was down to two cases, the one she owned and No. 26 on the stage, which contained $200,000.

At that point, the show's "banker" offered her $561,000 to stop playing. Deal or no deal.

"My knees gave out a little bit because that was so much money," Robinson remembered. "I was kind of torn. My strategy had worked. At the same time, I thought, 'Do I want to risk a half a million and maybe go home with $200,000?' "

So she turned to her family in the audience. All of them said, "No deal!"

Jessica figured it was a "win-win," she said. "I thought take the risk and go for the gi-normous amount."

She turned to host Howie Mandel and said, "No deal!"

He opened the case and . . .

"I see it, and I have no idea what happened after that," Jessica said.

"I know I didn't fall over. Within .2 seconds, everyone was around me - my family, the models - confetti is falling, and it's so loud. I thought, 'What is happening? It can't be real.' And it was."

The one moment in the game Ross Robinson cherishes most is when one of the cases revealed he and his wife are having a boy, a scheme made up by the show's producers and Jessica.

"It was probably the best part of the show for me," he said.

When the Robinsons get their winnings the beginning of next year (in one-lump sum, after about half goes for taxes, she said), the family will move to Austin, Texas, where her family lives, and buy a house.

Her husband will finally get a newer (but still used) truck, start a window-cleaning business, and they'll tuck the rest away for the kids' education and the family's future.

"But I am totally going shopping when I'm skinny again," Jessica said, laughing. "And there's no stopping me."

vince@sltrib.com