Arrow’ season 2 lets loose its fourth episode of the year with “Crucible,” as Oliver Queen learns the shocking identity of the mysterious Canary, ultimately teaming with her to take down a Glades warlord who terrorizes Sebastian Blood's efforts to save the city.

Last week’s ‘Arrow’ episode “Broken Dolls” saw Oliver partner with Officer Lance to find a doll-making serial killer, while Moira’s trial took a shocking turn, and Roy pursued Sin (‘The Killing”s Bex Taylor-Klaus) to find the mysterious Black Canary , revealing ties to some major DC players along the way, so what does the fourth episode of ‘Arrow’ season 2 bring?  Will Oliver finally become the hooded hero we know from DC comics?

Read on for your in-depth recap of everything you need to know about ‘Arrow’ season 2′s DC-heavy episode 4, “Crucible!”

Oliver finds himself late to a party at his own mansion, busying himself taking down a number of armed thugs in the Glades. Once he arrives to the festivity, Isabelle Rochev (Summer Glau) reminds him he needs to raise investor funds, before Laurel and Sebastian Blood interject to explain the ongoing Glades gun violence of “The Mayor.” Meanwhile, the man in question demonstrates his latest military-grade weaponry, shooting one of his own subordinates for losing a shipment to the Arrow.

Back at the party, Oliver notices that Laurel seems to be drinking more than usual, before Felicity interrupts with a revelation of her own: in their efforts to track down the Canary, they’ve wrongly assumed her to be following Oliver, when in fact, Laurel was also present at every appearance. Later that night, Oliver springs a trap for the Canary outside of Laurel’s apartment, unmasking her as none other than her sister Sara Lance (Caity Loitz), whom Oliver had thought to be dead.

Following Sara’s escape, Oliver admits to Diggle and Felicity that he had actually seen Sara a year after the sinking of the Queen’s Gambit, though he had been certain of her death otherwise, and thought it of no use to explain the true circumstances of her death to the Lances. Meanwhile back in the past, Oliver finds his freighter cell visited by a mysterious Captain (‘Heroes’ star Jimmy Jean-Louis) demanding information about the island, and the mysterious graves. Oliver brushes off his threats of torture and refuses to talk, for which the Captain non-fatally shoots Oliver in the stomach.

Back at the present Canary’s clocktower, Sara admits to Sin that her family wouldn’t recognize her even if they knew her to be alive, while Diggle meets with his old A.R.G.U.S. contact for intel on the Mayor's stolen shipment of military arms. Elsewhere, Oliver meets with Sebastian Blood to plan a cash for guns event to benefit the Glades, though Isabel Rochev reminds Oliver he needs to shift his focus to restoring the company rather than pay out of pocket for the event. Across town, Laurel agrees to dinner with DA Donner ('Orphan Black' star Dylan Bruce), but leaves when things get too flirtatious, and gets pulled over for a DUI.

Felicity manages to activate a homing beacon within the Mayor’s shipment of guns, allowing Oliver to infiltrate the man’s lair and at least seize the weapons, while the Mayor manages to escape. Back at her car, Laurel finds the officer in charge called her father to come pick her up, to which Quentin points out that she seems to be developing the same drinking problem he once suffered from, though she denies any need for help.

Sara visits Oliver at his club, though either refuses to share exact details of their last encounter, including the fate of Slade Wilson. Sara admits she came back to Starling City after the earthquake to watch over her family, when the pair are interrupted by Quentin’s arrival. Sara keeps out of sight as Quentin asks Oliver to talk to Laurel about her drinking problem, and Oliver nearly confesses the truth about Sara before agreeing to help Laurel. Back in the past, Oliver finds a pan of medical supplies waiting outside his cell, as his fellow Russian inmates reveal that they all endured the test of strength to patch up their own bullet wounds. Oliver manages to dig the bullet out of his abdomen, while the Captain realizes from Oliver’s reactions to descriptions of the graves that they’ve found the right Island.

Back in the present, Laurel brushes off Oliver’s attempts to show concern for her behavior, just before the cash for guns event begins in the Glades. Roy offers up several weapons, getting mocked by Sin for dating the rich Thea Queen while he’s at it, as Oliver arrives to oversee the event with Sebastian Blood. Oliver solicits Blood's advice about a pair of sisters who continually refuse his help, to which Blood remarks that those who go through a “crucible” either survive, die, or become addicted to the pain. Suddenly, the Mayor and his crew drive through and shoot up the event, as Oliver barely manages to pull Blood out of a hail of gunfire, one bullet of which ends up hitting Sin.

Footage of the shooting allows Felicity to identify the Mayor as Xavier Reed, a man whose foster brother has military ties that provided the weapons, and will introduce a more powerful shipment into the Glades later that night. Later, Roy watches over Sin in recuperation at the hospital, while Oliver finds The Canary suited up and ready to help him score payback against the Mayor.

The Mayor greets his foster brother and the military convoy delivering the shipment, though the deal is swiftly broken up by a two-pronged attack from Oliver and Sara, the latter of whom manages to get the drop on the villain, though Oliver convinces her to spare his life. The next day, amid news of another S.T.A.R. Labs particle accelerator protest, Blood pays a visit to Oliver to thank him for his efforts with the gun drive, and in saving his life.

Sin regains consciousness and reluctantly admits to Roy that she approves of Thea, while outside in the corridor Oliver confronts an inconspicuous Sara. Oliver presses Sara to show her family that she survived, while elsewhere Quentin attends and A.A. meeting worried about Laurel, who continually downs pills and wine. Back in the past, Oliver is dragged from his cell into the freighter’s medical bay, where out steps a figure prepared to torture him, none other than the surviving Sara Lance.

Back in the present, the Mayor awakens tied to a chair by a police officer, and a menacing masked figure who injects him with a “miracle” drug designed to make him stronger. The drug unfortunately kills the Mayor, for which “Brother” Blood unmasks himself as Sebastian, and demands the compliant police officer fetch him another subject.

OUR REVIEW:

Understandably, there would have been no way to live up to the excitement of last week's "Broken Dolls" which managed to elevate an effective -- if standalone -- story to dizzying heights by virtue of all the DC connections and revelations. "Crucible" doesn't necessarily aim to top that peak, though it still manages to end up with a fairly effective story in its own right. It remains unclear if 'Arrow''s producers ever truly expected to keep "The Canary"s identity a secret, what with the vigilante figure undoubtedly bearing some connection to the Lance family, and repeated leaks of actress Caity Loitz's role, though the revelation adds some unexpected wrinkles to the mythology.

More than that, "Crucible" looks to tweak the show's own mythology base as a whole, given that Oliver's apparent knowledge of Sara's survival seems out of line with the guilt we saw resonating throughout the first season, however brief their reunion may have been aboard the freighter. By the same token, it could bear fruit that Oliver seemed unwilling to address Slade's fate to a Sara that apparently knew him, though the audience knows that Oliver's secrecy serves the series moreso than the story.  Having flashbacks work in tandem with a present narrative has always been a tricky tightrope to walk, and we're bound to see a few more frays along that wire, even as the inherent excitement of a more super-powered plot patches them over.

We're not entirely surprised to see Sebastian Blood outed as a more overt villain either, here tweaking the character's cultish DC origins with a dash of 'the Batman Begins' version of Scarecrow, though we're glad to see the cards on the table, rather than focus on the somewhat clumsy reveals. We can clearly see the super-sci-fi bleeding in around the edges of the series, throwing in yet another 'Flash' foreshadowing as the past Oliver gets a taste of a larger mystery, one likely connected to the same "miracle" we saw Brother Blood experimenting with later. "The Mayor" ends up being of little consequence to the greater story, however unique the character seemed for a one-off appearance, though the end more or less squeaks by in justifying the means.

Of course, addiction storylines have historically proven dicey in lending sympathy to characters in need of something to do, so we're less sold on further explorations of Laurel's new vices. The first four episodes proved largely successful in bringing the character to some much-needed realizations of her own culpability in the events of the first season, so hopefully the producers can find a more organic path for the character beyond wallowing in self-pity. A minor blemish on an otherwise-successful episode, but "Crucible" seemed a bit rougher around the edges than its predecessor, even in smaller aspects like the choppy fight-choreography, so we'll avoid begrudging for the moment.

Well, what say you?  Did you feel that ‘Arrow’ hit the mark with its second season’s latest offering? Were you surprised by all the major revelations of “Crucible”? Give us your reactions in the comments, and join us next week for another all-new ‘Arrow’ recap of season 2, episode 5, “League of Assassins” on The CW!

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