Actually I can't on here so...
SPOILER ALERT.......................
Kinvara and Raff were having an affair, he convinced her to be involved in a plot to kill his dad so they could be together (and pocket the inheritance).
What she didn't realise was that the painting they made all the noise about was worth £20million. Raff didn't love her and it was all a ploy for him to marry her then kill her so he inherited everything. He had hidden it in the attic so it wasn't sold with the rest of the belongings.
Raff tricked Robin into meeting him (she thought she was meeting Matt) on a canal boat and was going to kill her but hot Cormoran kicked the door in and rescued her. He called Raff a cowardly fuck then punched him (swoons).
Turned out the person that the lad from the beginning (can't remember his name) saw being strangled on the horse was Raff (he had long hair), being abused by his brother who then killed Raffs pony and that is what was buried.
The blackmail was in connection with gallows that the bloke from agents of shield's (Jimmy?) dad was making for Chisell. He made him carry on exporting them after the ban on export of torture equipment and one of their gallows was stolen and used by terrorists to execute a young lad which was recorded and shared online. Jimmy(?) wanted his cut of the money and threatened to expose Chisell. Geraint wanted his own back on Chisell because his son Freddie(?) was an abusive arsehole to Geraint's daughter.
But mainly, there was a really cute moment with a hug / near kiss.