He was the child of Staron as well as the grandchild of T'Pring and Stonn. At some early point in his life, he was initiated into the secretive conspiracy that consisted of the Symmetrists along with his grand parents who were both co-conspirators in their plans. By the year 2373, he was placed on Ambassador Sarek's staff and became an aide to Spock who taught Srell like a mentor as well as like the son he never had. Srell worked with Spock during his mentors attempts at bringing about Reunification with the Romulan race.
In the same year, the Virogen Crisis erupted which threatened to destroy the United Federation of Planets. Initially, Srell was with Spock and served as a valuable counsel when his mentor received a holoprojector message from Sarek's aide Ki Medrossen about being part of a "cause" and being somewhat responsible for Sarek's death. After the Federation Council declined to meet secret representatives from the Romulan Star Empire on Babel, Spock decided to determine the validity of his father's murder which he thought was by Bendii syndrome but turned out to be an artificially induced pathogen.
Srell arranged for Spock's transportation to the Gonthar Distract on Vulcan where his mentor met his uncle Tarok who was also suffering from Bendii syndrome. Whilst attempting to find out who his father's murderer was, the compound was attacked by unknown enemies. In the midst of the chaos, Tarok was taken to safety by his two Klingon nurses but they were killed and Srell held the dying elderly Vulcan in his arms. At the time, the young Vulcan along with Spock, James T. Kirk, Christine MacDonald, Andrea M'Benga and Barc were all arrested by the Vulcan authorities for suspected mutiny. After the disguised Kirk claimed he was allergic to Tellarite fur from Barc, Srell exchanged places with his mentor to a neighbouring holocell where he remained until an escape was planned. During his time in detention, he informed Kirk of possible Vulcan terrorist cells that had existed in their history and gave examples of the Adepts of T'Pel, Binaries, Kahrilites, Followers of the Cupric Band, Traxton Compound and the Central Source. When Spock also mentioned the Symmetrists, Srell attempted to deflect blame away from them stating they were just an ecological group and had been distorted by not being entirely consisted of Vulcans.
He helped his comrades escape the holographic detention area that mimicked the Surak Memorial and journeyed with his fellow escapees to enter the USS Tobias which was impounded in the spacedock. However, an umbilical had been attached to the Oberth class ship preventing its escape. Srell along with Spock and Kirk attempted to disengage it when the Vulcan guards came onto the scene. Srell ended up in a fight with the guards allowing Spock and Kirk to escape but not before his mentor witnessed Srell being killed by a phaser blast. This act of seeing his student killed had a dramatic impact on Spock who began to let his emotions dominate him. He later informed Representative Stonn and T'Pring of Srell death though they showed no sign of loss on their expressions when Spock told them of their grandson's demise.
Later, when the crew of the Tobias and the USS Enterprise-E under the command of Captain Jean-Luc Picard arrived at Tarsus IV they learnt that the Symmetrists were involved in the Virogen plague which they were creating the Tarsus colony. Arriving on the world and its secret base, the Starfleet crew were attacked by Symmetrist defenders which Commander Christine MacDonald attempted to draw their fire. During this attempt, she was captured by the Symmetrists; one of whom was Srell himself. Thus, Spock learnt that his student was actually a Symmetrist and had been assigned to Spock in order to cover their actions from him. Furthermore, he revealed that he was responsible for Sarek's death due to his belief in the "cause". Kirk and Spock participated in a mind meld with Srell in order to learn the truth of the events that had unfolded.
After a brief struggle against Spock which left Srell bloodied, the young Vulcan came face to face with Kirk who held a phaser rifle by him. Srell taunted Kirk from memories he had plucked from Kirk's mind during the meld and that he would never kill in cold blood. At that point, Kirk fired the phaser just as an explosion erupted by the Virogen storage tanks. Srell was killed when he was consumed in the fire though it was unclear whether Kirk or the storage tank had claimed his life. Kirk later commented that he believed he was responsible for Srell's death due to his intent on firing the phaser. (TOS novel: Avenger)