This article contains spoilers for the Arrow season six mid-season finale, 'Irreconcilable Differences'.
Arrow picked up after the Crisis on Earth-X crossover having a reception for Oliver and Felicity, where a few very interesting things happened. Curtis got drunk, Rene gave a very nice speech, and Quentin had a father/son moment where he gives Oliver the watch his father gave him. And Donna Smoak showed up with Noah Kuttler, AKA the Calculator, and Felicity's father as her date. Its a very nice reception (save for Curtis's speech) — until Quentin gets a call from Jean Loring, Oliver's attorney, who tells them that the FBI has a member of Team Arrow willing to testify that Oliver Queen is Green Arrow. The night goes downhill from there.
Oliver talks to Felicity and Diggle about it and decides to spy on the others instead of bringing them in and talking — which, of course, goes poorly. Meanwhile, Quentin is taking Thea home when they are confronted by Black Siren, who easily kicks the out-of-practice Thea's butt and takes Quentin. She leaves Thea with a phone that rings just as she gets to Oliver. Cayden James has taken him and wants a one-of-a-kind piece of tech that will amplify the bomb he's making and Argus has it.
Spying on the rest of Team Arrow showed Dinah meeting with the Vigilante, so they assume it's her and leave her out as the rest of the team breaks into ARGUS and take the device. They decide to sabotage it before turning it over. Then Dinah shows up and asks why she wasn't called in — Oliver confronts her and she denies it. Things get heated, and Rene shuts it down by admitting he is the one that flipped. Rene is kicked off the team, but Thea convinces Oliver to give him another chance. Meanwhile, we get a moment between Black Siren and Quentin where we learn about her father and how he died.
The full team goes to do the exchange — except James already knows the device has been sabotaged. He orders Black Siren to kill Quentin. Wild Dog and Mr. Terrific disobey orders to stay where they were and go looking for Quentin, and are then out of place to back up Green Arrow when called. Siren chooses to not kill Quentin and escapes. They get Quentin back safely, but Oliver is angry that he gave Rene a second chance and he disobeyed. He kicks him off the team again, except Dinah agrees about needing trust between team members in the field. And since they didn't trust her and spied on her instead, she quits. She ends up going to Vince, AKA Vigilante, to talk. We see Rene go home with his daughter. Curtis decides he can't trust them, either, and leaves the team. This leaves only the original Team Arrow left, and we see the James has a camera hidden in the bunker.
The episode had a lot of surprises. Seeing Kuttler appear was interesting and makes me wonder if he'll help out against James later in the year. The watch scene with Quentin and Oliver was a nice touch to show how much the two characters have changed over the years. Nice moments like that also tend to pop up before someone dies… so the writers made the threat to Quentin seem very real. The Rene twist was interesting because it fits in with the them of fatherhood that has been going through the season. That's why Oliver gave him a second chance — because of what he did for his daughter.
And with the final scene, we see Cayden James talking with Black Siren and his henchman. They are then joined by Anatoli, Vigilante, and Ricardo "the Dragon" Diaz. Meet your bad guys team just as Team Arrow is at its weakest. I keep expecting to find that Agent Watson is part of James's plan, as well. And I'm doubting that James really did anything to Alena — her going to Felicity is more of the plan. Should be a lot of fun when the show returns on January 18th, 2018.