Sully (Kane Robinson) killed Jamie (Michael Ward) in the season finale of Top Boy. Sully never trusted Jamie.
Jamie and Sully are rivals and sometimes ally. Sully always disliked Jamie.
Dushane (Ashley Walters) framed Jamie for weapons possession then worked to secure his release from prison in return for Jamie working for him.
Dushane’s actions implied that he is considering Jamie as his retirement plan. Dushane and Sully have got different ways now and Sully is determined that he will not let his rival take the position of Top Boy.
Top Boy Season 2 (closing scene)
Jamie is at home with his brothers Aaron and Stefan. A knock at the door, which Jamie leaves the dinner table to answer and the unexpected visitor is Sully. Sully shoots Jamie twice in the chest.