Little is known about Warren's life. Vidic had been working for Abstergo since at least 1982. He was not a typically happy man, and was driven by his constant work. Warren led the Animus project, but left the assembly and engineering of the Animi up to his co-worker on the Animus project, Lucy Stillman, and the Abstergo engineers.
Around 1985, Vidic started to experiment on Subject 4, a young boy who would later be given the alias "Daniel Cross". Vidic put Cross in the Animus to relive the memories of his ancestor, though he also experimented on Cross with a replica "Piece of Eden". Cross also had a secret impulse embedded into his subconscious that would drive him to assassinate the Mentor of the Assassin Order, should the opportunity to do so arise. In 2000, Cross met with the Mentor of the Assassin Order in their headquarters located in Dubai, where he unwillingly killed the Mentor. He returned to Abstergo Industries' headquarters in Philadelphia, where Cross' own memories were used to find all the Assassin camps and exterminate the Assassins.
Vidic and Lucy Stillman both worked on, who was a pregnant woman. They had difficulties with the animus because it was trying to read the fetus' father's genetic memories as well as Subject 15’s memories.
Vidic grew tired of the slow progression of synchronization to access further memories, so despite Lucy's warnings, he put Subject 16 in the Animus for days on end in search of answers until he started suffering from the bleeding effect. Subject 16 suffered from constant mingling of lives of his ancestors to the point of insanity, where he allegedly committed suicide.
In the year 2012, Warren Vidic held the position of head of genetic research at Abstergo Industries; part of his role included looking after test subjects for his Animus project. That year, he authorized the capture of the seventeenth test subject; a bartender named Desmond Miles. At first, Vidic found the new test subject both unwilling and, subconsciously, not confident enough to explore his ancestor's memories. Vidic only managed to gain his cooperation after threatening a coma and an inevitable death.
Despite Desmond's cooperation, however, progress was slow. Vidic's assistant, Lucy Stillman, was overly protective of Desmond's health because of what happened to Subject 16, and insisted on only short sessions within the Animus, lest their latest test subject begin to hallucinate as the previous subject did. Disheartened but compliant, Vidic ordered Desmond to his quarters and left the laboratory.
After witnessing the death of Al Mualim and activation of the Piece of Eden in Desmond's genetic memories, Vidic recorded the map displayed within the memory, commenting "We've got it". As Desmond awoke, he saw three suited individuals in the laboratory's conference room. The three begun discussing with Vidic the results, and insisted upon Desmond's execution; Vidic agreed, but was cut short by Lucy, who insisted that Desmond's use had not yet ended. The two argued to the point of Vidic claiming that Lucy was undermining his authority, and Vidic stubbornly agreed in Lucy's assessment to let Desmond live; to "leave nothing to chance". Ordering Desmond back into his room, Vidic left the laboratory.
The next day, Vidic received word of Desmond's escape, and the direct assistance Lucy had given him in executing it. Abstergo quickly set about tracking down the Assassins, and within three days had found the two in a warehouse and attempted to recapture them.
Locating the Hideout, Vidic took a contingent of Abstergo security guards to apprehend Desmond and Lucy, arriving just as Desmond finished exploring the memories of another of his ancestors – Ezio Auditore da Firenze. Cutting off the Assassins' escape, Vidic attempted to coerce Desmond into coming peacefully whilst berating Lucy for her apparent betrayal. The two rejected him, and so Vidic ordered his guards to apprehend them. Minutes later, following the death or incapacitation of his entourage, Vidic was confronted by Desmond at the rear of his vehicle. Desmond challenged Warren to step down from the vehicle and to stop his cowardice, but Vidic replied by commenting that the Assassins should enjoy their temporary victory, and fled, leaving the Assassins to find a new hideout.
After that, Vidic went on to initiate and train a team of Abstergo's loyal agents into more "subjects" like Desmond, through the use of several Animi, and the bleeding effect.