For two decades, Chris Beck was a senior chief with SEAL Team Six - the elite team who took out Osama bin Laden.
Today, after coming out as a trans woman in 2013, she goes by the name Kristin.
She is the first openly transgender former U.S. Navy SEAL, as well as the recipient of a Purple Heart and a Bronze Star. She is now running for Congress.
Before she revealed her true identity, her life was a lie, she said.
"No one ever met the real me. No one knew anything," she told CNN.
In 2013, she published a book, Warrior Princess, in which she talked about growing up and wishing she could live as a girl. But her dad was a man's man and expected her to serve in the military so she chose the toughest branch of all: the Navy SEALs.
"If I could be at that top level, maybe this would go away. Maybe I could cure myself," said Kristin.
She got married and divorced twice and had two sons. In between foreign deployments she made covert missions of her own - to Victoria's Secret to buy lacy lingerie.
Dr. Anne Speckhard, the co-author of Warrior Princess, told INSIDE EDITION: "Late at night [Kristin] would put on female clothes and sit and watch TV."
It horrified her wife, who said: “Please don't ever do this in front of our kids.”
At work, Kristin kept quiet about her real identity.
"If Kris had come out as transgender during her time in the SEALS, she would have been put out of the military," said Speckhard.
When Kristin finally came out as transgender, her Navy SEAL friends had mixed reactions.
Stuart Smith, a former Navy SEAL, told INSIDE EDITION: "I'm not saying it's right or wrong. I just don't understand the whole process of it.
"At the same time, he has a 20-year SEAL career and I have to support him for that."
Kristin says she decided to go public to encourage others to be who they are. She retired from the SEALs in 2011 with a Purple Heart and a Medal of Valor.
She is now mounting a Democratic primary challenge for a congressional seat in Maryland.
Kristin said: "I fought for 20 years I fought for life, liberty and the pursuit of happiness. I want some happiness."
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