From a young age, Radzen showed an aptitude for engineering. He would pull apart and reassemble almost any device he could get his hands on. Partly to help him to excel where he showed aptitude, and partly to save their household appliances, Radzen’s parents enrolled him in an engineering trade school on Trillius Prime. The boy thrived at the school and found a mentor in one of the teachers, Marida Tos. In his fifth year, Radzen began an apprenticeship under Marida.
Radzen finished his apprenticeship shortly after his eighteenth birthday and, with the encouragement of Marida and his parents, applied to Starfleet Academy later that year. He spent the next four years studying a variety of subjects, but focused on engineering. It was also during his time at the Academy that Radzen first saw Sherah Ch’prai. Ch’prai was finishing her musical tour of the Federation in San Francisco. She was a musical prodigy from Andoria and was skilled in numerous musical instruments and styles. Radzen fell in love with her the moment he saw her play. But Ch’prai returned to her teaching at the Aldebaran Music Academy and Radzen to his studies, without the two ever having met.
Early Starfleet Career
Utopia Planitia Fleet Yards
Fresh out of Starfleet Academy, Radzen was assigned to the Utopia Planitia Fleet Yards. He loved his time there, but soon received news that his old mentor, Marida, was dying. Taking a short leave, the young Trill officer returned home. He arrived in time to visit with Marida and learn that she wished for him to take her symbiote, Tos. Radzen had never seriously considered becoming a host, but he was assured that he qualified and could be joined if he so wished. He was hesitant at first, but his great respect for Merida Tos and his desire for knowledge led him to agree to host the symbiote. He was joined with Tos, shedding his old name and becoming Radzen Tos.
After returning to the fleet yards, Tos continued to enjoy his duties for a time. But he eventually became anxious to explore the galaxy. Finally, in 2392 he was promoted to lieutenant and transferred aboard the USS Tahoma. Radzen was assigned to the night shift and soon became friends with the shift’s senior officer, Commander Keval Ch’prai. During a resupply stop at Betazed, Ch’prai invited Tos to join him at a musical performance on the planet. It just so happened that it was a performance by Keval’s sister, Sherah. Radzen’s interest in the musician was rekindled and he was finally introduced to her. The two courted intermittently for three years before finally being wed.
The Archangel and Starfleet Academy
By that point, Tos had been promoted to lieutenant commander and was stationed on the USS Archangel. The starship served as an exploration and ambassadorial vessel. Sherah joined Tos on the Archangel and performed at many diplomatic functions. After a few years, Tos took a leave of absence to teach at Starfleet Academy. Sherah performed at various locales in the Sol System and taught music in Singapore.
As hostilities erupted with the Klingon Empire, Tos was called back to the Archangel, this time with the rank of commander and as the executive officer under his old friend Keval. However, during a particularly brutal confrontation with Gorn battleships, Keval was killed. With his dying breath, he gave Tos a battlefield promotion to captain. Due to his ingenuity and valor in rescuing the remaining crew, Starfleet Command made Tos’ rank official shortly after his return to Earth Space Dock. He was given command of the USS Epyon and was assigned back to Ktarn Fleet.
Command of the Gheryzan
After the development of the Odyssey-class cruisers, President Aennik Okeg decided to name a series of the new starships in honor of the member worlds in the United Federation of Planets. Tos was given command of the USS Gheryzan, which was named after his homeworld of Trillius Prime. Captain Tos and his crew would serve with distinction during the Undine and Iconian Wars. In the latter conflict, the Gheryzan was critically damaged and Tos and his crew were given an extended leave at the war's end. That was not the end of the Gheryzan however, as it was pegged for an upgrade and overhaul into the new Yorktown-class.
After three months of construction, the USS Gheryzan was recommissioned and Captain Tos was once more placed in command and reassigned to Ktarn Fleet.
- 2410-: USS Gheryzan (NCC-97017-A), Yorktown-class Block II/S star cruiser
- 2409-2410: USS Gheryzan (NCC-97017), Odyssey-class Block I/T star cruiser
- 2407-2409: USS Epyon (NCC-99013), Chimera-class heavy destroyer
- 2405-2407: USS Archangel
- 2400-2405: Starfleet Academy
- 2396-2400: USS Archangel
- 2392-2396: USS Tahoma (NCC-71651), Cheyenne-class heavy cruiser
- 2389-2392: Utopia Planitia Fleet Yards