Sergeant First Class Jack Kellar is the main character of the video game Black. His rank is Sergent First Class and is a Black Ops soldier for the CIA. He belongs in Bravo team. Despite being a great marksman (Depending on the player's skill) and fighter, he is somewhat rebellious, and often deliberately disobeys direct orders (Such as when he goes through the doorway after Lennox in the first level). He is never completely seen, except for parts of his face in the interrogation cutscenes.
Kellar is also a veteran of several conflicts including Guatemala, Colombia, Iran and Croatia. The unknown interrogator questions Kellar about an arms smuggling and terrorist operation called the Seventh Wave. Seventh Wave have been responsible for a number of terrorist attacks. Kellar is told that, unless he co-operates, he and his actions will be declassified, he will be dishonorably discharged and imprisoned for life. Though initially resistant, Kellar at last agrees to tell his story.
Four days earlier, Kellar and his group were assaulting a Seventh Wave stronghold in the city of Veblensk. Kellar kills three high-ranking members of the cell but then disobeys orders by rushing inside a terrorist controlled building, where a terrorist ambushes him. However, the man did not kill Kellar, who learned that his captor is an American, William Lennox, a former CIA wetworks operative. After faking his own death in Cairo, Lennox has apparently become the leader of Seventh Wave.
Kellar's next mission is to cross the border into Treneska and traverse the Vlodnik Canal, destroy a base and weapons cache, then meet a female black ops soldier named MacCarver, the leader of black ops Team Bravo, at a farmhouse. Things do not go as planned; however, Kellar defends and clears the farmhouse and later meets MacCarver.
Kellar and MacCarver begin a mission to destroy an arms factory in the city of Naszran. To safely complete the mission they must navigate an old graveyard and town, both heavily defended. After doing so, they assault the town's iron foundry, destroying its productive capacity. The two black ops then meet a third member of the team, Solomon.
Based on information gathered from the mission, Team Bravo has proceeded to a well-defended dockyard, cleared the area and linked up with Alpha Team. Alpha Team, however, is destroyed in an ambush while Lennox escapes seconds beforehand. In light of the disastrous result, the operation is cancelled as well. Despite these events, Kellar leads a retaliatory assault against the Graznei Bridge before leaving his team at the gates of Lennox's compound to successfully penetrate the defenses both around and inside the Spetriniv Gulag. During the attack, Keller triggers an explosion resulting from the destruction of two concrete barricades, and subsequent explosions in the final room of the underground bunker, presumably killing Lennox.
The interrogator then reveals to Kellar that authorities had, in fact, always known of Lennox's involvement in Seventh Wave. Kellar had acted predictably, doing what his profile said he would, and his pursuit of Lennox was both expected and welcome - and that Lennox is not yet dead. Kellar is told that a false "death" has been arranged for him, providing cover so he could continue his pursuit. The game ends with Kellar being told to get ready for his next assignment.