Just finished watching the last episode. So now we know:
How Baptiste's leg was injured - slammed in a car door by Ziane.
Why Ziane is in prison - assaulting Baptiste and being involved in an unsolved murder (I think) in a Morocco that Malik's dad had evidence of.
What happened to the evidence from the drain - Ziane gave it to Malik for 24 hours, but rather than returning it so that it could form part of the investigation Malik has kept it. Probably so that he can make millions by revealing the solution to the case in his book.
How Ian got away with murder - sank Ian's body at sea, set the boat adrift, put his bloody shirt in concrete. Then Baptiste made sure he was there 8 years later when the concrete was broken up, nabbed the shirt and gave it to Tony.
Tony and Emily are still together 2/3 weeks after Ollie's disappearance but not for much longer now she knows he murdered Ian, I suspect.
Does anyone have theories about the following:
Have we met Baptiste's daughter before?
Who is implicated by the drain evidence? Malik reacted as if it was significant. Malik seems to be chasing Vincent. Does this mean it implicates him?