The identity of Sully's killer in Top Boy is deliberately left ambiguous and was never revealed in the show. The series ends with Sully being shot by a mysterious figure in a black hoodie, but the culprit is not shown on screen
. Several suspects have been considered by fans and analysts:
- Stef : He had strong motives since Sully killed his brother Jamie, but Stef ultimately spared Sully when he had the chance and the killer’s clothing differs from Stef’s
- Si : A rival gang member who had been humiliated by Sully and might have had reason to kill him, possibly shooting him in a quick walk-by
- Bradders and his associates : Bradders was left to bleed out by Sully and might have sought revenge if he survived, or his crew could have killed Sully on his behalf
- Jaq : She had personal reasons to want Sully dead to protect her family and avenge a murder
- The McGees (Irish gangsters) : Sully and Dushane killed two members of this powerful crime family earlier in the season, so they might have retaliated by killing Sully
- Erin and Mandy (or hired hitman) : Since Sully killed Erin’s father, Dris, they might have arranged for Sully’s assassination, though they are unlikely to be the direct shooters
The show’s director confirmed that an alternative ending revealing the killer was filmed but chose to keep the identity a secret to emphasize the dangerous and unpredictable life Sully led, where many enemies could have been responsible
. In summary, Top Boy ends with Sully’s death as an unresolved mystery, reflecting the brutal and uncertain nature of the street life portrayed in the series
