The search for a killer named Digger Harkness brings Arrow, Arsenal and Diggle into conflict with an ARGUS team that is also hunting the dangerous criminal. Luckily, The Flash is on hand to offer his help. But Harkness is more than just a terrorist - he's a former Suicide Squad member with a grudge against Lyla Michaels and a coat full of special boomerangs that make him more than a match for The Arrow. Bringing him down may require The Arrow to do some things The Flash doesn't approve of... like enhanced interrogation of the local thugs.
In the flashbacks, Amanda Waller begins training Oliver Queen in the fine art of tortu- ah, enhanced interrogation techniques.
The Brave and The Bold comics of The Silver Age, but also every single story where a jaded veteran butts heads with an idealist newbie. This has been the story behind literally hundreds of comics stories but perhaps the most famous modern example of this sort of thing is the rivalry between Superman and Batman, as seen in the animated movie World's Finest.
When Caitlin shows up in Felicity's office, she refers to Canary as Sara, despite Felicity being very careful not to identify Sara Lance by name in F108 where she asked Caitlin for help in identifying a DNA sample.
While Barry is quick on the uptake to save Ollie from Captain Boomerang's attack in the first fight scene, he doesn't do anything to stop the villain from throwing down a smoke bomb and running for it.
Granting that they have a high-tech metal detector that trips almost immediately upon Digger Harkness entering a secure area, it still seems strange that a group as security minded as ARGUS only has one guard watching the entrance to their headquarters.
Again, it's hard to single out any one cast member for particular praise as everyone does a damn good job playing off one another. But David Ramsey may come the closest to stealing the show, playing John Diggle with a bit more verbosity than we're used to seeing.
The first fight scene with Captain Boomerang vs. Arsenal and The Arrow is amazing. And then The Flash shows up and it becomes better.
The episode's title - The Brave and The Bold - comes from a classic DC Comics book series. Originally started in 1955 as a showcase book for stories about Robin Hood, The Silent Knight and The Viking Prince, the comic would later come to depict the stories of the original Task Force X (aka Suicide Squad) and superhero team-up tales - usually Batman paired with another member of The Justice League.
The Brave and the Bold contained a number of significant stories during its run. The Justice League of America's first appearance was in The Brave and The Bold #28 (March 1960). The first appearance of The Teen Titans (or at least the first story pairing up Robin, Kid Flash and Aqualad which inspired the Teen Titans monthly comic) was in The Brave and The Bold #54 (July 1964). And Green Arrow's first appearance with his Robin Hood-inspired costume and social-justice-warrior attitude came in The Brave and The Bold #85 (Sept. 1969).
The opening and closing shots of the show's logo features the word 'Arrow' being bisected with a stylized lightning bolt like in The Flash's symbol.
The ARGUS agent killed in the last episode is identified as Kai Wu. He is named in tribute of Kai Yu Wu - a writer on The Flash TV series, who co-wrote A104 with Geoff Johns.
Felicity's office is bigger than Cisco's apartment.
Cisco asks if The Arrow has an Arrowmobile. In the comics, Ollie did indeed call have a special car for crime-fighting that he called The Arrowmobile.
In the comics, George "Digger" Harkness (a.k.a. Captain Boomerang) is an enemy of The Flash as well as a frequent member of The Suicide Squad. Born of a traveling toy salesman's affair with an American army wife in Australia, Digger grew up abused by his mother's soldier husband, who knew full well that George was not his son. This imbued young George with a life-long disrespect for authority. The only bright-side to George's life was the one thing his birth father gave him - a toy boomerang that he learned to throw with great skill. Embittered by years of abuse, he turned to petty crime and was kicked out of the house, spurring his mom to give him a plane ticket to Central City so he could be with his father. Once there, Digger was put to work as Captain Boomerang - a mascot for his dad's toy company. But the toy company was failing and George turned to crime in earnest after one too many of his paychecks bounced.
The Arrow/Flash version of Digger Harkness is a former ASIS agent (presumably Australian Secret Intelligence Service and not American Society for Industrial Security) who went rogue - a weapons and technology expert. He was caught by ARGUS three years earlier and recruited for Task Force X aka The Suicide Squad. Like Captain Boomerang in the comics, he is fond of making jokes about boomerangs always coming back when he kills people.
In terms of skill, Digger Harkness is to boomerangs what Oliver Queen is to arrows. In the comics, Harkness makes use of all manner of trick-boomerangs as Oliver Queen uses trick arrows.
Putting together a puzzle at super-speed (in this case, the fragments of Digger Harkness' exploding boomerangs) is another standard Flash trick from the comics.
Quentin mistakenly calls Barry "Bart Allen". In the comics, Bart Allen is the name of Barry's grandson, who fights crime with his super-speed powers using the codename Impulse.
Harkness is hiding in a warehouse on the corner of Infantino and Adams. This is a tribute to both Neal Adams (the artist who created the look of the Bronze Age Green Arrow) and Carmen Infantino (the artist who created the Silver Age version of The Flash). Infantino is also the artistic creator of Black Canary and his first credited professional work was the story in Flash Comics #86 which first introduced Black Canary as a partner for Johnny Thunder.
A villain hiding multiple bombs around a city, requiring a superhero team to split up to defuse them all is one of the oldest comic book tropes of all time and a particularly frequent problem for speedster heroes like The Flash.
The Arrow is able to identify the armored but not identified soldiers as ARGUS by their flanking patterns, which he notes they haven't changed in years.
The Jettisoning Arrow uses compressed CO2 to jettison high tensile-strength polymer cables.
Digger Harkness' exploding boomerang is made of a 3D printed polymer with a circuitry weave. The grooves in the boomerang are capable of holding a C4 charge.
Cisco identifies the exploding boomerangs as the work of a weapon's designer named Klaus Marcos. The collapsible node design is his signature.
Harknesses bombs are radio-controlled IEDs - improvised explosive device.
Caitlin notes that some of the STR markers on the DNA sample of Sara's killer are gone, but she has a computer program that can fill in the gaps.
Cisco makes a new shirt for Oliver made of a polymer-Kevlar weave. 25% lighter and capable of carrying 15% more gear.
The Arrow: Drop your guns.
ARGUS Agent: Sure thing. Right when you learn how to count. You're outnumbered, jerkwad!
The Arrow: You're not SCPD.
ARGUS Agent: Unless police uniforms have gotten really interesting, neither are you.
The Arrow: ...ARGUS. Your flanking patterns haven't changed in years.
(Regarding Cisco and Caitlin hanging out in their base)
Roy: Since when did we start selling admission to The Arrow Cave?
Ollie: It's- (bites his lip before pointing at Felicity) Do you see what you've done?
(Regarding the Salmon Ladder)
Caitlin: Hey, what's that for?
Felicity: (sighing happily) Distracting me from work.
Harkness: You know, you should be careful how you treat people, my friend. After all... (throws boomerang, which kills the ARGUS guard) ...what goes around, comes around.
(Watching Barry Allen work The Salmon Ladder at super speed)
Caitlin: How often does Oliver do this?
Felicity: At least every Wednesday. There's a lot of sweating.
Barry: I need some dinner. That salmon ladder made me hungry for sushi.
(Barry runs off and a gust of wind knocks all the papers off Felicity's desk.)
Felicity: And I need to get some paperweights down here!
(As Barry runs into the Arrow cave, maskless, in front of Lyla)
Caitlin: Hey! Secret identity?
Barry: They're married!
Lyla & Diggle: We're not married.
Barry: Or together. Whatever. He told her about me.
(Diggle shakes his head)
Barry: You didn't?
Diggle: I keep secrets for a living, man.
Barry: Ah. My bad.
Caitlin's wordlessly pulling away Cisco's phone as he tries to take a picture of Ollie and Barry together without their masks.
(As The Arrow enters a warehouse to find The Flash standing next to six tied-up, unconscious mobsters)
Barry: I had eight seconds to kill!
Barry: You tortured that guy.
Ollie: I interrogated him.
Barry: When my friends said your tactics made you a criminal, I defended you because I thought you were supposed to be a hero. I thought we were supposed to be better than them?
Ollie: Barry, you live in Central City. Where it's sunny all the time and your enemies get cute nicknames! You're not in Central City. I live in a city where my best friend was murdered! Where a woman that I loved was shot full of arrows and sent tumbling off of a rooftop! Where my mother was murdered right in front of me! So before you-
Barry: My mother was murdered in front of me too. But I don't use my personal tragedies as an excuse to just torture whoever pisses me off!
Ollie: Well, I'm sorry Barry. I'm not as emotionally healthy as you are.
Lyla: Everything alright between you and Speedy?
Ollie: (confused) What? Roy? Yeah. We're fine.
Lyla: I meant him (looks at Barry)
Lyla: Sometimes bravery isn't enough. Sometimes the world requires us to be bold.
(As Ollie enters the warehouse to find that Barry has, once again, tied up all the thugs)
Barry: You're late.
(Ollie shoots the thug who comes up from behind Barry)
Barry: ... I knew he was there. He's not dead, right?
Ollie: Tranq Arrow. Same thing I used on you in Central City.
Harkness: You know what I like best about boomerangs, Lyla? They're proof that things can always come back to haunt you!
Waller: There are people in this world who deal only in extremes. It is naive to think that anything less than extreme measures will stop them.
Ollie: To do what I do takes conviction. But more often than not it's the will to do what is ugly. Every time I do that I'm trading away little pieces of myself. So... you ask what's wrong with me. That's what's wrong. Because the part of me I'm trading away is Oliver Queen. And lately I've been feeling like there's nothing left except The Arrow.
Barry: I think you're full of crap. Look, you've convinced yourself that everything you've been through took away your humanity. But I think it's because of your humanity that you made it through! You wouldn't have survived, much less come out the other end a hero - somebody that wants to do good - if you didn't have a light inside of you.
Cisco: Screw you, Captain Boomerang!
And every single instance of Diggle calling Lyla "sweetie" and her responding that he only calls her that when he wants something and every moment someone prompts them - or anyone - to declare that they aren't married. All so they could build up to this moment...
Diggle: Hey Sweetie.
Lyla: You only call me Sweetie when you want something.
Diggle: I do. I want you to marry me. I can't believe I waited this long to ask. I need you, Lyla. Now. Forever. Officially. I need you-
Lyla: Would you please stop talking so I can say 'yes'?
The man killed by Digger Harkness in A307 was an ARGUS agent named Kai Wu.
Using a residue from the boomerang Oliver Queen gave them in F108, STAR Labs was able to track Digger Harkness to a certain address in Starling City.
Felicity says they do not call the basement they operate from The Arrow Cave. Ever. This is exactly the same way Ollie answered the question when Roy Harper asked if they called themselves Team Arrow in A212.
According to Cisco, the events of F108 occurred one week before this episode.
Barry refers to the lessons Ollie gave him in casing a crime scene before running in a week earlier and how he's been practicing.
Ollie's connections to the Russian mob are referred to, though Ollie notes that after his falling out with them in A206 he's probably no longer a member.
Ollie makes reference to the Tranq Arrow he used on Barry in F108.
Cisco installed a miniature video camera behind the emblem in Barry's costume.
Barry makes reference to Multiplex - the self-cloning villain from F102.
Diggle proposes to Lyla.
Digger Harkness is locked up in the ARGUS prison complex on Lian Yu. Ollie says that he and Slade Wilson are now roommates but this probably isn't literally true.
Felicity makes reference to the landmines on Lian Yu, which nearly killed her back in A201.
Ollie sets up a third mannequin in the Arrow Cave to hold Barry's costume when he is in town.
Cisco makes Oliver a new shirt/quiver.
STAR Labs industrial fabricator was based out of Starling City.
The Fridge Factor
Averted somewhat. While all the female members of the cast are imperiled at one point, Lyla Michaels fights back against Digger Harkness and even Felicity tries to take him down with a small explosive. Of course Caitlin and Felicity are non-combatants but they prove their worth to the team later on, with Caitlin's medical training being essential to saving Lyla's life and Felicity tracking down Harkness' location.
The Winick Factor
Barry could have taken down Digger Harkness pretty easily at the beginning of the episode if he hadn't stopped to smile at Ollie after catching the boomerangs that nearly killed him. Just saying...
The Bottom Line
Perfect. Just perfect.