03E22 - The Bitter End

Danny gets a call to go to a project where a gang rules with fear and intimidation. Jamie finds a girl standing on the roof holding her baby, saying she can't stand their lives being controlled by street gang Los Lordes so she jumps to death with her baby. Danny later learns that the girl was someone he met when she was younger when her parents died and he said he would help her and her sister. Danny goes to her sister who is bitter that Danny forgot about them. He learns that she is now with the leader of the gang. While Jamie and his partner are walking through the project there's some shooting and Jamie's partner is hit. Frank later learns that the D.A. is not pressing to prosecute the gang so Frank goes to the mayor for help.