What is the storyline with Finn and the rohypnol about?

[DiaDuit]

This guy targetted Finn, knew his name and was looking for him and then drugged him and tried to kill him. What's it about? It doesnt make sense.

I'm guessing Ross has upset someone and they are wanting revenge. Maybe the jewellers family?

Ahhh! Good thinking! I was wondering if it was something to do with their mum, maybe 'brad' was another son she'd had but your theory sounds far more likely.