History Recap / ArrowS4E9DarkWaters

* GenreSavvy: Felicity knows the BigBad isn't dead if you NeverFoundTheBody.

* AwLookTheyReallyDoLoveEachOther: Thea does a PinkySwear with Malcolm Merlyn after [[EvenEvilHasLovedOnes he asks her to be careful]]. It's a sign that, regardless of her estrangement from him, Thea is still drawn to Malcolm as a father despite what she said in "The Return".

* AwLookTheyReallyDoLoveEachOther: Thea does a PinkySwear with Malcolm Merlyn after [[EvenEvilHasLovedOnes he asks her to be careful]]. It's a sign that, despite her estrangement from him, Thea is still drawn to Malcolm as a father despite what she said in "The Return".

* IdentityImpersonator: Felicity points out that Oliver surrendering himself--even to find out where they are being held prisoner--is stupid because Darhk is bound to wonder why TheCavalry doesn't include the Green Arrow. Turns out Malcolm Merlyn has no problem donning the costume to help rescue his daughter.

* ThreateningShark: Used for a CommercialBreakCliffhanger when Oliver is swimming back from the ''Amazo''. However it just takes a nasty bite and then [[RealityEnsues ignores Oliver because he's not to its taste]].

** Laurel learns that her father is Oliver's ReverseMole in H.I.V.E.

* {{Cliffhanger}}: In the island flashback, Oliver and a NotQuiteDead Tatiana have been caught by Conklin. In the present day, an attack on Oliver's limousine by the Ghosts leaves Felicity heavily injured in the final scene, and we don't see the aftermath.

* InstantExpert: Oliver brings Tatiana to the ''Amazo'' because she's a diving instructor, but some short instruction is apparently all it takes to enable Oliver to free dive down there and find what he's looking for. Penetration diving (in this case, swimming inside a wreck) is a high risk activity because you can't just surface if you get into trouble. At the very least Oliver should have had Tatiana along with him.

* WhereTheHellIsSpringfield: Damien's dialogue explicitly places Star City on the West Coast, ignoring hints in prior episodes that it was in the Midwest. This tends to indicate Central City is also situated more toward the West, otherwise the characters (including Barry) wouldn't jaunting between them so nonchalantly.

* KickThemWhileTheyAreDown: During a montage of the Green Arrow trying to get information from the Ghosts, he's shown repeatedly kicking a Ghost after he is down, [[HeWhoFightsMonster something that had seriously disturbed Oliver when Thea was doing it]].

* BadBoss: Damien Darhk [[TestedOnHumans tests his gas chamber with the help of a willing HIVE minion]]. This is despite the fact that he intended to gas Oliver's friends anyway and so could have just used them.

* TheBusCameBack: Milo Armitage the man who hired Bronze Tiger to steal Merlyn's earth quake machine in Season 2's "[[Recap/ArrowS2E12Tremors Tremors]]" comes back as one of Darhk's partners.

** When Curtis's husband says that straight people leave the wedding ring in the soufflé, Felicity realises that Oliver planned to propose in "Green Arrow" when he insisted she have dessert (before Thea and Laurel interrupted).

* ShootTheTelevision: When Oliver gives a press conference exposing Damien Darhk and HIVE to the world, a television broadcasting this suddenly shatters, followed by a shot of Darhk glowering at the ruined screen, having presumably broken it by magical means (or just the force of his DeathGlare).

* AwLookTheyReallyDoLoveEachOther: Thea does a PinkySwear with her supervillain father, after [[EvenEvilHasLovedOnes he asks her to be careful]]. It's a sign that despite her estrangement from Malcolm Merlyn, Thea is still drawn to him as her father despite what she said in "The Return".

* WouldHurtAChild: The HIVE helicopter drone opens fire on the clean-up regardless of the fact that there are children there. Only a DivingSave by Oliver stops mini-Felicity from being shot, and more would have died if Felicity hadn't hacked into the drone and caused it to crash into the bay.