Tryan was a Talthun engineer on the Stromos during its trip to Ardena before it crashed. He was apparently acquainted with chief engineer Pharrin, as both recognized each other by name, with Tryan possessing a significant respect for Pharrin's technical skills, commenting that only he could achieve what had been accomplished.
When the ship's systems began to fail after a forced crash-landing, he was one of the twelve minds that were transferred into the body of Dr. Daniel Jackson in an attempt to preserve the minds of the Talthuns whose bodies had died, but the transfer process was unstable, causing the various personalities in Daniel to randomly shift control. While trying to determine what had happened to Daniel, Dr. Janet Fraiser was eventually able to talk with Tryan. Although shaken at the knowledge that his body was almost certainly dead, and apparently rather humble about his knowledge, Tryan was able to explain to Janet about how the systems responsible for the transference worked, using the analogy of water molecules in a glass to explain why they couldn't simply transfer the minds back into the machine. Although he lost control of Daniel again during the conversation with Janet, he was later able to assert himself once again, reflecting that he appeared to have a greater pain threshold than the other personalities- ironically including his own arrogant Sovereign Martice- that made it easier for him to remain in control for longer.