It’s becoming a well-known phenomenon that the midseason finales of long-running shows have to pull out something big to encourage viewers to come back after what is in some cases an unreasonably long hiatus. In this case, Arrow has really gone to town, and “The Climb” provides some major shocks and some fairly hefty revelations, as well as bringing back a much-loved villain from earlier seasons.

The episode opens up with Oliver, having just dropped off a Christmas present for Captain Lance in the form of a slightly beaten-up criminal, being accosted and trussed up by the League of Assassins. He is taken in front of Nyssa, who informs him that Ra’s al Ghul’s patience has run out, and that if he is unable to deliver Sara’s killer to the League within 48 hours, they will start murdering citizens of Starling City. Not only that, but she passes the responsibility on to a member of the League who removes his mask and reveals himself to be none other than Maseo, Oliver’s reluctant mentor from the Hong Kong flashbacks.

That’s revelation number one.

So the pressure is on to find Sara’s killer once and for all, and the DNA markers found on the arrows seem to be the best lead the team has. However, the results match up with the Starling City Police Department database and show that it was Oliver’s DNA on the arrows, originating from perspiration found on them. Obviously this means that someone is setting him up, and the most obvious choice is Malcolm Merlyn, probably in an attempt to put Oliver at odds with the League of Assassins.

So Felicity uses some A.R.G.U.S. information tracking flight traffic in and out of countries of interest, with a flight tracking from Corto Maltese all around the world and ending up in Starling City the night before Sara’s murder. Oliver manages to use his powers of violent persuasion to get security footage of the airstrip, and finds that Malcolm did in fact arrive in Starling City that night, but he also brought Thea with him.

Felicity points out that a match for Oliver’s DNA on the arrows could also be a match for Thea’s DNA, and that the points of entry for the arrows on Sara’s body could have come from an archer of Thea’s height. So Oliver confronts his sister, smashing through the window of her apartment in full costume, where he discovers that his little sister has learned how to look after herself to the tune of a face full of broken glass and a young lady leaping out of the window.

And finally, we get answers as Malcolm pays a visit to Verdant and reveals everything: in order to erase his blood debt with the League of Assassins, he needs someone to kill Ra’s al Ghul, and he believes Oliver has the best chance of doing it. So he used what amounts to a mind-control drug to get Thea to murder Sara, giving Oliver incentive to tell the League that he was the one who killed Sara and face a trial by combat against the leader, all in order to protect Thea from Ra’s al Ghul.

That’s revelation number two, and three if you count the fact that Malcolm Merlyn has shown that he has in fact been a villain all along: not the brutal father/mentor who is ultimately only concerned about the safety of his family, but a manipulative psychopath who will do anything to protect himself.

Unfortunately, this manipulative psychopath’s plan has worked perfectly, and Oliver readies himself: he goes to meet Nyssa who takes him to Ra’s al Ghul, and he confesses to Sara’s murder. He challenges Ra’s to a trial by combat, and even though Ra’s states that it has been 67 years since someone challenged him (and yet, he doesn’t look 67…perhaps there is something a little bit supernatural going on), Oliver confirms his challenge, and Ra’s accepts. Maseo tells him to meet at a consecrated League location, but gives him enough time to say his goodbyes, to Thea and Team Arrow respectively.

But before we get to the climax, let’s take a look at some of the other story threads this week: Laurel gets an unexpected Christmas present in the form of her mother paying a visit to Starling City, and Dinah realises that Sara is dead. Laurel explains what happened to her, and Dinah essentially tells her to exact whatever vengeance is necessary, and to destroy the person responsible. It’s a pretty bold statement from a woman who used to be married to a cop, but it also feels like one of the last things Laurel really needed to become the Black Canary: all she needs now is the costume!

Elsewhere, the simultaneously creepy/charming Ray Palmer takes a moment to explain himself to Felicity: turns out, his fiancée was killed during the Mirakuru riots at the end of last season (and I do like the fact that we are slowly seeing more ramifications of that as we go through this season) and Felicity was the first person he kissed since that happened, hence guilt and running away. He also explains that he wants to be able to protect people, and so everything he has been doing with the company has been to create an exosuit which has state of the art technology shrunk down to fit in the palm of his hand: the A.T.O.M. suit (revelation number four). However, as interesting as this is, the best part of this scene is Felicity exclaiming that she ‘has a type’, and she absolutely does: she’s attracted to all of the superheroes!

Meanwhile, in the Hong Kong flashbacks we get the explanation of why A.R.G.U.S. needs to stop Chien Na Wei: she is planning to use an engineered super-virus for some dastardly purpose, and uses a scientist (controlled with the same natural chemical Malcolm used to control Thea) to steal it. She then breaks into Maseo’s house, has a brief swordfight with Tatsu, and then takes her somewhere: fortunately she leaves their son, but it’s a bad day for Maseo either way.

Finally, the climax of the episode: Oliver goes to the duel, and after a gruelling climb to the top of a mountain he is ordered to remove his shirt and choose his weapon. A brief, but extremely well-choreographed and shot duel ensues, and just as it seems like Oliver is gaining the upper hand Ra’s catches a sword blade-first with his bare hand, and stabs Oliver right through the FREAKING CHEST. He gives him the usual villainous ‘this is a good, noble death’ speech, says a prayer for his soul, and then simply kicks him off the edge of a cliff.

Fade to black.

WHAT THE HELL, ARROW?! That’s what you’re leaving us with?!

Verdict: 9/10

There’s not much more to say about this episode than this: episode 10 can’t come soon enough.