So,
It really feels like the writers just don't care anymore. Its like they realized that Arrow fulfilled its purpose by giving the world an awesome superhero show (The Flash), so now they've just kind of given up and are just writing whatever stupid thing comes to mind first. Its weird how far Arrow has fallen. The only good episode this season was the Flash team up. Maybe Season 4 will be better. It almost certainly can't be worse than this season.
Oliver gives in to brainwashing faster that I would have expected humanly possible. Seriously, I haven't seen anyone get mentally dominated this quickly or lamely, especially the supposed hero of the story.
He then tries to kill his friends and is going to go along with Ra's plan to force a woman (who we know isn't willing) into marrying him. He'll also probably try to kill all of Starling City now, I guess. But, knowing this show, Felicity will probably end up saving the day by bringing Oliver back to his senses with the power of love
There was also flashback stuff, but every single flashback in arrow this season has been painfully bad, so I've been mostly just ignoring it for the last few episodes.
He then tries to kill his friends and is going to go along with Ra's plan to force a woman (who we know isn't willing) into marrying him. He'll also probably try to kill all of Starling City now, I guess. But, knowing this show, Felicity will probably end up saving the day by bringing Oliver back to his senses with the power of love

There was also flashback stuff, but every single flashback in arrow this season has been painfully bad, so I've been mostly just ignoring it for the last few episodes.