Silik was a senior official in the Suliban Cabal during the 2150s. In that capacity, he led the Cabal in fighting on the 22nd century front of the Temporal Cold War.
Silik took his orders from a mysterious humanoid figure who communicated from the 28th century. In exchange for doing his bidding, this individual provided the Cabal with the technical expertise necessary to genetically enhance themselves. These enhancements included shapeshifting, enhanced senses, and the ability to survive in extreme environments. These enhancements gave Silik a distinct advantage over those he opposed.
In 2153, after Earth suffered a devastating attack which resulted in the deaths of seven million people, Silik abducted Archer from Enterprise under orders from his master and delivered him to a temporal communications chamber. There, the Cabal's benefactor provided Archer with intelligence that the Xindi were behind the attack, and that they were working for another faction in the Temporal Cold War. This gave Starfleet the information it needed to mount a mission to stop the Xindi from destroying Earth.
One year later, Silik was assigned to stowaway on Enterprise, when his master learned that Daniels would be sending it back in time to 1944 to stop the Na'kuhl, another Cold War faction, from constructing a temporal conduit. Wanting the ability to physically travel through time rather than just communicate through it, the Cabal's benefactor ordered Silik to steal the conduit's specifications and deliver it back to him. Silik was discovered, however, and eventually teamed up with Captain Archer in order to stop the Na'kuhl. They were eventually successful in destroying the conduit before the Na'kuhl had a chance to use it, but Silik was shot to death in the process. His final words to Archer were an admission that Archer had proven to be a worthy adversary, and he would have preferred to die fighting Archer.