|Known Relatives:|| Evelyn Mercer (adoptive deceased mother)|
Bobby Mercer (adopted brother)
Angel Mercer (adopted brother)
Jeremiah Mercer (adopted brother)
|Portrayed By:||Garrett Hedlund|
Jack Garett Mercer was put up for adoption as a child when nobody else wanted him. Evelyn Mercer adopted him, as well as Bobby Mercer, Angel Mercer and Jeremiah Mercer. Jack is the youngest brother of the four.
Jack grew up with his adopted brothers, with their mother raising them to be good people. He hated yelling and violence because of the abuse he suffered at the hands of his real parents when he was just a child. He was a little different from the other brothers, because he preferred rock music and wanted to be in a band. He was credited as a punk rocker and loved his adoptive mother Evelyn. He even got a tattoo to honor her. When the brothers got older Bobby left Detroit, Jerry stayed and married his wife, Camille, eventually having kids, Angel left to join the war, and Jack started pursuing his g music career. Evelyn was at a convenience store to buy some turkey when two men came in with guns, demanding money and shooting the man at the register. Evelyn was hiding, but the men found her and shot her as well. Jack and the rest of his brothers reunited at their mother's funeral awerh
Jack, Bobby, Jerry, and Angel wanted to hunt down their mother's killers despite a warning form the police. The brother's first wrecked a party (though Jerry desired to stay behind and not participate), and got information from a kid that someone had paid a witness to lead the cops off the real killers trail. When the brothers visited the convenience store where their mother was killed they watched the video where she was murdered. Jack seemed the most upset by the video than any of the others. The man who let them in gave them a description of the paid witness, and told the brothers where they could possibly find him. The brothers then led their investigation to the gym where a basketball game was in progress. Bobby interrupted the game, waving a gun and shouting out the description he was given at the store. At this time, a young boy got out of his seat and attempted to leave. Jack saw him and chased him, Angel helping by blocking the door Jack was chasing him out of and catching the boy. Jack got Bobby's attention, and they went to question the boy. Turned out the paid witness was the boys brother, and after going through his bookbag the brothers got his address, where they decided to wait for Damien. They chased after him for a while, Jack helping by telling the brothers what floor Damien was going to. Damien tried to escape through his window, but the brothers cut his rope, and the six story fall broke Damien's leg. The brother's questioned him as he was stuck in the snow, and threatened to leave him to die several times. Damien eventually game them the information they needed, and they left. When Bobby, Jack, and Angel caught up with the killers they managed to flip their car. Bobby told Jack to stay back, and Bobby and Angel killed the guys that killed their mom. Jack flinched and looked away as he heard gun shots.
Victor Sweet found out about how the two killers were rammed off of the road and killed. The Police investigated this as does Bobby's old friend Lt.Greene and his partner Fowler. The two detectives interrogated Bobby at the Mercer house and the brothers denied having anything to do with the murders.
Jeremiah informed the brothers that his construction company was failing precisely because he was not getting involved with Victor Sweet and that for a project to succeed he had to pay off the right people, which he initially failed to do. In his effort to restore his business and relieve pressure from himself, he tried to pay off Sweet's henchmen. As for the life insurance, Jeremiah explains that the money went directly to him for his 2 daughters, because he paid all of Evelyn's bills while his other brothers were not around. A knock on the door was heard and Jack answered it only to get a snow ball thrown at his face by a random stranger. Jack chases the stranger who turns around and is revealed to be wearing a hockey mask and shoots Jack. A shootout ensues as Jack calls for Bobby. The brothers eventually win and come to Jack's aid. having Sophie (Angel's girlfriend) calls 911, but Jack dies before they are able to arrive.