Coca-Cola's biggest secret is now hidden in plain sight.

Well, sort of.

The Atlanta-based company, with pomp, circumstance and some dramatic billowing smoke, unveiled a newly completed vault at the World of Coca-Cola, where the formula that changes fizzy sugar water into one of the world's top drinks is now housed.

The formula, which had been under lock and key since 1925 at SunTrust Bank, was placed inside the vault several days before by Coke Chief Executive Officer Muhtar Kent.

"Today, we are going to unlock some of that magic," Kent said Thursday after videos teased the years of mystery surrounding the ingredients and fans' attempts to replicate Coke. "The time has come for the secret formula to come back home."

Dignitaries, including Gov. Nathan Deal, Mayor Kasim Reed. Martin Luther King III and relatives of one-time Coke owner Asa Candler, were then ushered into a new exhibit. They passed a wall featuring rumors about the formula (only two men know the secret and they can never travel together, goes one) before coming to the vault itself.

Tim Mescon, an economist and president of Columbus State University, said such dramatics were perfect Coke theater. The mystery behind the formula is a marketing strategy Coke has used to great effect, especially since today's sophisticated chemists can probably figure out the formula's content.

"It is what this global empire has been built on," Mescon said. "It is basically part of the Coca-Cola tradition. The fact that we're talking about it shows how they can create a national buzz without spending advertising dollars."

Coke has been working on the exhibit for months, directing the few who knew about it to sign non-disclosure agreements. Even after the unveiling, the company remained mum on details, including the vault's size, its security strength, or the square footage of the expansion and its cost.

The company moved the formula at the request of the board of directors, a spokesman said. The idea was to cap the company's 125th anniversary, which Coke has been celebrating all year, with something dramatic.

Jacquie Wansley, a spokeswoman for the World of Coke, said the exhibit is more interactive than the rest of the facility, with an emphasis on putting visitors in the mystery of the formula.

It also will help the attraction bring out visitors who haven't been to the exhibit in a while. More than 1 million people annually visit the World of Coke, which turns 5 in May 2012.

"There is not about collectibles archived behind glass," she said. "There is very little of that. This is experiencing Coca-Cola in a new way."