Walking out to the beach, Adrianne Haslet looked like any regular guest at the Four Seasons Papagayo: pale skin, dark sunglasses, wide-brimmed straw fedora with a black band.
Until, that is, she stopped to take off her leg.
"Prosthetics and water don't mix," she said, as her husband, U.S. Air Force Major Adam Davis, lent an arm to help her hop over the shifting sand to the water, where the red and white dive boat pitched in the surf.
Dive instructor Ernst van der Poll then scooped Haslet up and carried her the last few steps into the water and over the side of the boat.
Haslet and Davis were both injured in the Boston Marathon bombing on April 15, 2013. The blast cost Haslet her left leg, but through her efforts and the support of others, she visited Costa Rica in February to complete her advanced open water scuba certification and fulfill a lifelong dream: to swim with sharks.
-- The first dive
Haslet held her hat in place as the boat motored out to the day's first dive site. A camera crew took shots and conducted brief interviews with the couple for a CNN documentary about Haslet's first year as a survivor.
At the mouth of Culebra Bay, Haslet sat in the boat readying her gear, pulling on her wetsuit and buoyancy control device, and checking the air tank. Leaning her head down to the valve, she called over one of the diving instructors to report a hissing sound. As they changed out her tank, she rested with the remaining part of her injured leg demurely crossed over the other.
Then came the duct tape.
"We already ran out of pink," Haslet said, settling for the classic silver adhesive.
After slipping a gel sock over her residual limb, one of the instructors brought over a dive flipper and held it in place over the sock as Haslet wound the tape around the flipper, securing it in place.
"Duct tape should sponsor us," Haslet hinted. She said they used a third of a roll on average to secure the flipper before each dive.
That day was only their second time diving in open water. The waves were choppy and the wind whipped. The Costa Rican boat captain said to no one in particular that they might have to cancel the dive if conditions didn't improve.
But Haslet and Davis were on a schedule. They had to complete their advanced open water certification before their next boat left from the Pacific port of Puntarenas for Cocos Island, one of the most famous and challenging dive spots for hammerhead sharks.
-- She loved to dance
Before the bombing, Haslet worked for the Arthur Murray Dance School in Boston for four years, teaching classes and fox trotting around the country competing in ballroom dance competitions.
"Adrianne always had passion and threw herself into whatever she was doing," Davis said. "She always liked working with people and then when she became a dance instructor, she threw herself into it. She felt like she was helping people."
On April 15, 2013, Haslet and Davis went to watch the Boston Marathon. Walking away from the finish line on Bolyston Street, they heard the first explosion. Just as they turned to see the cloud of smoke rise from the finish line, the blast from the second pressure-cooker bomb hit them.
The bombing claimed the lives of three and injured 265. U.S. authorities are seeking the death penalty for Dzhokhar Tsarnaev, then 19, for his alleged role in the blasts. The trial of Tsarnaev, a Chechen Muslim, begins in November.
Tsarnaev's brother, 26-year-old Tamerlan Tsarnaev, died in a gun battle with police after a four-day manhunt following the bombing.
Davis was hit with shrapnel in his right foot and suffered nerve damage. The blast severely damaged Haslet's left leg. Both their families rushed to Boston to help their children.
"We couldn't have asked for better parents," Davis said.
Doctors recommended amputating Haslet's injured leg below the knee and she eventually agreed.
After the amputation, Haslet had to relearn her daily routine and push her limits on her own.
"For me, it's learning where I can support her and where I don't need to do that," Davis observed. "I always want to protect her and help her out, but at the same time [let her] keep her independence."
Despite her quick smile and snarky wit, Haslet admitted that she struggles.
"I just allow myself to feel it, you just have to be emotionally honest," she said in a telephone interview. "There are some days when I just need to lose it."
But she pointed out that she also relied on friends and family to shake her out of the dark place and get her moving, even if it was as simple as leaving the house for a cup of coffee.
For Haslet, that meant getting back on the dancing floor.
-- An MIT scientist takes interest
After the attack, Haslet and her family went to a lecture on state-of-the-art prosthetics and what the future could hold for artificial limbs at the Spaulding Rehabilitation Hospital in Boston. That's where she met the speaker, Dr. Hugh Herr of the Massachusetts Institute of Technology.
Herr grew up in an adventurous family. Traveling across the United States they explored the outdoors, fly fishing, canoeing, hiking and mountain climbing. Herr started mountain climbing at the age of seven.
When he was 17 years old, Herr and his family were climbing Mount Washington in Vermont when a storm kept them on the mountain days longer than they had anticipated. After days on the mountain, frostbite had gnarled his legs.
Doctors worked for months to save his legs before finally surrendering the fight. Herr had both his legs amputated below the knee.
"I was fitted with the technology of the time and was amazed by how unsophisticated it was," Herr said. "I immediately started designing."
After specialists fit him with prosthetics, Herr immediately started to tinker with them. Soon, he designed his own prosthetics and was climbing mountains again.
He still climbs today.
Herr threw himself into the science of bionics. He heads the biomechatronics laboratory at MIT, where they have developed an artificial knee for people with above the knee amputations and a foot ankle, among other inventions.
After the talk, Haslet approached Herr and the two became fast friends.
"[Haslet has a] progressive attitude, her outlook on life, her willingness to experiment, to take the next step, pardon the pun," Herr told The Tico Times.
Haslet was in much the same situation as Herr had been years ago, left with a prosthetic that was ill-equipped to handle the challenges of a mountain face or, in her case, the dance floor.
Dancing relies on the performer's ability to move the ankles, point toes and lead with the toe or heel. Conventional prosthetics use an ankle fixed at 90 degrees that makes this impossible.
"Dancing [with a prosthetic] is different in about a 100 million ways," Haslet said. "You want your body to do something it did before, and now it can't."
Herr was intrigued by the challenge to develop a dancing limb and offered the resources of his laboratory at MIT to develop a prosthetic that would allow Haslet the full spectrum of motion required for ballroom dancing.
Herr envisioned a prosthetic with a muscle-like motor system to move the ankle during dance controlled by algorithms downloaded into a microchip in the artificial leg.
After development started on the dancing limb, Herr asked Haslet what else she wanted to do.
"Dive with sharks," she said.
Eight months later they would be in Costa Rica.
-- Dream comes true
Davis said that they both had an interest in diving but doubted they would have pursued it without the push of the bombing.
"My dad really got into diving when I was younger, so I had a pretty good idea that I would like it," Davis said. "But Adrianne has always loved sharks."
"I used to take time off work when Shark Week came on," Haslet said.
Herr reached out to friends who put them in touch with van der Poll, a diving instructor based in Playa del Coco, Guanacaste, who specializes in disabled diving.
Van der Poll made some calls and within weeks had convinced the adventure company Undersea Hunter to sponsor the Boston couple and Herr for a one-week dive to Cocos Island.
Cocos Island, located over 300 miles off the Pacific coast of Costa Rica, is famous for its sharks, especially schools of hammerheads.
The uninhabited island's green cliffs rise dramatically out of the ocean, leading French diving legend Jacques Cousteau to famously call Cocos "the most beautiful island in the world."
Back at the boat, bubbles floating to the surface of the sea showed where the divers were rising to the surface.
"We saw a guitar shark!" Haslet yelled, bobbing in the waves after she breached the surface.
It wouldn't be her last. On Feb. 1, Haslet, Davis, Herr, and van der Poll boarded a boat in the Pacific port of Puntarenas bound for the remote natural reserve.
There, they swam with hammerheads, tiger sharks and spotted rays. They saw a humpback whale with its calf. Van der poll said the water was some of the clearest he had ever seen.
After returning from Cocos, Haslet said she wanted to keep diving and start doing public speaking to raise awareness about adaptive diving and moving on after a life-changing injury.
"Diving means the world to me. It's easy to think about what you can't do, especially on those dark days," she said, but to be able to dive "you feel that sense of accomplishment, especially after a time when you thought you never would."
In March, she realized another dream when she performed on stage for the first time publicly since the bombing. She took the stage at the 2014 TED Conference in Vancouver, British Columbia, with a new prosthetic limb.
"Dancing a diving are actually very similar," Haslet said. "Dancing may not come naturally to someone -- diving almost never does -- and you need to trust your instructor and push your comfort zone. But once you get a hang of it, it's poetic and beautiful."
AFP contributed information about the bombing to this article.