Pralisi ir'Kelhuan t'Shelhnae was a young citizen of the Romulan Star Empire, daughter of parents who ranked highly in the Tal Shiar. Pralisi was deeply proud of her family and groomed from a young age to follow in her parents' footsteps. By age 8, her tradecraft was exceptional and rivaled many students twice her age. By 10, she was widely considered a prodigy and an asset to the Tal Shiar. She began taking on assignments, to the pride of her parents.
Pralisi would be sent to ordinary schools and manipulate the other children into revealing their family's secrets. She would be placed into "foster" care to spy and report on her hosts' activities. For two years she was extremely successful in rooting out subversives, criminals, and terrorists. Then, Romulus was destroyed.
The Tal Shiar fancied themselves the glue that held the Empire together, and while the Federation tried to relocate citizens they labeled "refugees," and D'Tan began forming his own group of terrorists, the Tal Shiar grew crueler and more heavy-handed. For the good of the Romulan people, of course. It was a time of crisis, and extreme measures were called for.
In an effort to undermine the Federation, her Tal Shiar handlers formulated a plan to place Pralisi in the care of another foster family. Not a Romulan family, but a Vulcan one. She was immersion-trained on Vulcan customs and philosophy and teachings. She was made to learn the Vulcan language, which she did in only a matter of months. A cover story was crafted for her, and agents of the Tal Shiar set to work planting details about her in computers throughout Starfleet and the Federation.
When the time was right, a small group of warbirds were sent to attack and capture a Vulcan science vessel with orders not to destroy it. All hands were killed, and data was introduced into the ship's computers that Pralisi - or T'Pral, under her new Vulcan name - had been aboard at the time of their departure from a remote colony world, returning to Vulcan after a long archaeological expedition. Everyone aboard was killed, and T'Pral was beamed aboard and told to find a place to hide and wait for rescue. Tal Shiar agents initiated a distress call, and left the system.
T'Pral was alone among the dead for eight days before she was "rescued." At age 13, she reasoned a Vulcan child would not stay hidden and cowering for long. So she explored the ship and got to know it as intimately as she could. She identified the two dead Vulcans woven into her cover story to be her parents, and dragged all the bodies to the cargo bay. She then set about a routine, eating, sleeping, bathing, and monitoring the ship's damaged sensors as best she could for approaching ships. She even added her own face and words to the distress signal.
"I am T'Pral Nkneva Kalkun aboard the V.S.S. Vulkyrs. We were attacked by several ships that vaguely resembled birds - Romulans, Captain Ralock called them. Everyone is dead. I am the only survivor. I know this because I searched and collected the dead in the cargo bay, which I have evacuated to preserve the bodies. Power is failing. Replicators have ceased functioning. All that remains is life support, gravity, and sensors. I calculate that if I do not receive help, I will be dead within six days."
As it turns out, a Starfleet patrol had already heard the distress signal and were en route. She was found by the U.S.S. Antwerp just thirty-two hours later. The ship's dead were transfered with respect and solemnity, and T'Pral was provided medical care, new clothing, and quarters of her own. She was given counseling, but she had adopted the deadpan, emotionless persona of a Vulcan girl. Her lack of grief or pain was genuine, but it was interpreted as typical Vulcan mental discipline rather than an indication that she'd never known her "parents" before their death.
The Antwerp delivered her to Vulcan. There was a great deal of bureaucracy involved, and she participated in the funerary rituals shortly before being adopted by a pair of Vulcan scientists. T'Pral quickly learned that not only were her adoptive parents not involved in any actions against the Romulan Star Empire, they weren't military, nor diplomats, nor connected to government except in the most cursory way. In fact, they never left the planet. In short, her mission was being thwarted not by being found out, but by being placed with two of the least useful people on Vulcan.
For a time, T'Pral tried to expand her connection the the community, to her new parents' colleagues, and to anyone official with whom they came in contact. Her efforts were fruitless. For a time longer, she tried to conceive a way to contact the Tal Shiar, but doing so from the Vulcan homeworld was extraordinarily risky. She would have to find a way off world to make contact. For years, no opportunities presented themselves.
Finally, she decided she would move boldly: she would join Starfleet. It wasn't that she hated her adoptive family - far from it. They were kind and gentle and, of course, highly logical. In truth she came to care for them quite deeply. Even in their emotional detachment they were kinder and more caring parents than her own had ever been. Her own parents saw her only as a tool, and later a trophy - a symbol of their parental success to hold up before their superiors to gain favor. T'Pral was learning what life outside the Empire was like, and if she were being honest with herself, she was coming to prefer it.
Of course, her adoptive parents expressed concern over her leaving Vulcan to join Starfleet. T'Pral had excelled in the sciences and the logical choice, they argued, was for her to apply to the Vulcan Science Academy. T'Pral committed to studying science at Starfleet Academy, however, and soon was on her way to San Francisco. In her head, she continued to focus on her goal of manufacturing an opportunity to travel outside Federation space to contact the Tal Shiar. Secreted in her heart, though, she was unsure whether that was still what she wanted.
Her time at Starfleet Academy only served to further erode her resolve. At Starfleet, she made friends. Actual friends, who cared for her and didn't demand loyalty or encourage deceit or expect quid pro quos. Just genuine friends. When the Federation-Klingon War started, and the little Malachowski she'd been assigned to for her cadet cruise was ambushed, command fell upon T'Pral's shoulders - and her crew trusted her to get them through after their captain had been captured and killed. It was in the immediate aftermath of that experience that T'Pral resolved never to return to the Romulan Star Empire or the Tal Shiar.
She has risen through the ranks of Starfleet since then. After being catapulted 150 years into the future, and aiding in the discovery of a Dyson sphere, she was given command of one of the brand new ships designed with Dyson sphere technology. The ship was christened the A.R.W. Fraternum - a Romulan design to pay quiet homage to her erstwhile home, but named "Brotherhood" in both the Romulan and Earth Latin languages, which T'Pral found befitting of her new outlook on the galaxy and her feelings toward Starfleet and the Federation.