From Star Trek: Theurgy Wiki
Tatiana Marlowe was an engineer aboard the USS Harbinger before transferring to the USS Theurgy in 2381. She replaced Alexander Rosek as Chief Engineering Officer when he was put in stasis after sustaining fatal injuries on Theta Eridani IV. Marlowe was later wounded when a saboteur caused an explosion in Main Engineering and died after surgery when further sabotage deactivated her biobed causing it to miss blood clot that stopped her heart. She was replaced by William O'Connell as chief engineer before she died. Before her death, Tatiana Marlowe aided in the opposition against the parasites that compromised Starfleet Command in the end of the 24th century.
Although Tatiana was not the first of her family to join Starfleet she was the only one since her grandfather. She had grown up listening to his stories and ‘tinkering’ with his vintage Aston Martin car. Her interest in the engineering of the internal combustion engine began her on the trail of a career in Engineering. She was not one of the naturals at it but instead had to work hard to get where she wanted to be.
The Academy was a hard time for her, she never felt like she truly fitted in with the others. The way she saw it they were all gliding through where as she was struggling to keep her head above water, while this was untrue in reality it did make her work hard and play only a tiny amount. While she would occasionally go out she spent most of her time studying to keep up with the classes. The hard work paid off in her results, graduating in the top 20%, but she had no really close friends from that time.
Her assignments have been varied from starbases to ships: the USS Heng, the USS Asterion and Starbase 63. Her most recent posting on the Harbinger has also been her most testing. Firstly with the split from the Federation, with her loyalty split she felt lost and alone for the first time, her family at home would think her dead or worse, a traitor, and she had no way of contacting them to let them know the truth. Secondly with the showdown that left so many of her colleagues dead, those she had become close to during her time aboard were suddenly gone and again the split loyalty caused her to question everything she knew. Thirdly was Alexander Rosek. Not only was he an obnoxious individual, in her opinion, but he was promoted above her. Not even her work was a refuge from the psychological pain caused by the events on board this ship. Being the professional however she gritted her teeth and worked harder than ever, returning to her quarters on the planet each night to work on her miniature model engine that runs on alcohol.
Tia missed her Akira-class vessel. The Theurgy-class Theurgy was very advanced but also a nightmare to repair. With the Harbinger there was a certain amount that could be bodged together to at least limp to a safe location but the Theurgy was so perfect it was flawed. The A.I. was also a nuisance, interfering and making suggestions. Supposedly it was trying to help but Tia just found it to be a distraction.
After Alexander Rosek was wounded and placed in stasis, Tia was promoted and assigned his position and given the Starfleet Medal of Commendation by Captain Jien Ives for her heroic actions on Theta Eridani IV. She was not chief engineer long before she was injured when Crewman Dom Fok sabatoged the plasma regulator controls in Main Engineering and caused an explosion. During her surgery, mind controlled mutineers under the control of T'Rena took sickbay hostage and shut down the Theurgy’s automated systems, including biomed monitors. She died from a simple blood clot that stopped her heart that the biobed could have detected and neutralized had it been functioning.
An introverted woman, Tia Marlowe could be obsessive, especially about her work and tended to withdraw when her personal life became complicated - she often came off as a cold person. She found it difficult to relax, tending instead to focus on complex, detailed tasks that allowed her mind to wander.
She had a burn scar running down her neck, chest and upper arm on her right hand side caused when an open can of the fuel her grandfather was using in the car exploded. The can had been sitting near a faulty electrical supply which shorted and sparked, igniting the vapours. The scars were a reminder that anything can and will happen no matter how safe you think you are.