Long before Warner Bros.' Justice League hits the big screens, The CW's own small-screen version is already well underway.  In part one of The Flash / Arrow crossover, Barry Allen gets first billing in "Flash vs Arrow", which will conclude with tomorrow night's Arrow hour, "The Brave and the Bold."  While it was certainly fun seeing both of DC's live-action TV heroes share some screentime, tonight's hour also managed to mutually progress the plots of each individual series.  And although one of the final scenes hinted at big changes coming up for Mr. Oliver Queen, this episode was all about Barry Allen and the many challenges he faces as a young up-and-coming crimefighter.

Hit the jump for The Flash recap.

The Flash kicks off the first part of this crossover episode giving a lesson in love as a citywide matchmaker. Meanwhile, a red-eyed meta-human manages to make people around him turn violent against each other while he strolls into a bank's vault and makes off with bags of money.  The Flash saves one would-be victim, but it too late to catch the guy in the act.

Speaking of getting caught in the act, we catch Eddie and Iris in bed, though they shut it down quickly so that the former can get to work, and the latter can check on her blog.  How contemporary!

Back at the bank, Joe is asking Barry to try and explain the outbreak of mass chaos, while Eddie is doing his best to convince the captain that The Flash is a menace to the city.  (Keep this plot point in mind.)

Barry heads to S.T.A.R. Labs to check in with the brainiacs about the latest meta-human problem, who appears to be controlling people's emotions.  We're about to get the first clash between Flash and the new baddie; and while Barry saves the cops from each other, guess who shows up to lend a hand (and a bow and arrow)!  Annnnnnd he's gone again just as quickly as he came.

Felicity and Diggle have great reactions to Barry's arrival, who beats Oliver back to their meet-up in the rain.  Ollie isn't convinced that Barry is up to the challenge of being a crimefighter.  It sounds like Team Arrow is in Central City to track down Captain Boomerang (because it's a rusty city...), and they plan to team up with S.T.A.R. Labs and Barry to catch two jailbirds with one stone.  Felicity's cool with the science geeks, but Oliver and Diggle plan to stay in the shadows.  At the same time, Joe West and Dr. Wells don't think Barry should be looking to the vigilante Arrow for heroic guidance, and they want him gone.  (Iris, however, is quite happy to have Oliver Queen in town, especially since he's on her list of guys she can cheat on Eddie with. How sweet.)

Get ready for a training montage!  Oliver's taking Barry to task for his laziness in crimefighting.  He plans to shoot Barry with an arrow ... make that two arrows.  Good thing Barry heals fast!  Oliver makes his point that Barry doesn't take the time (which he has in spades) to case every angle of a crime scene before engaging.  While Oliver is certainly a bit on the crazy side (at least according to Joe), Barry still stands up for him and his method of getting results.  Wells tries another tactic by going through Felicity to confess his mistrust for Arrow, and to find out his secret identity.  What's he up to, playing some future Find-the-Arrow game?  (Yeah it doesn't take a super-genius to figure that one out, and Wells gets it before too long.)

The team-up comes with some new upgrades thanks to Felicity and they're able to track Bivolo to his apartment.  Barry runs off without Arrow's support; bad move, since he plays right into Bivolo's hands as he awakens anger within the young crimefighter.  Apparently it didn't work (or it has a delayed effect, morelike), since the lab scanners find no damage.

Time for Round 2 of Training Time with Arrow and Flash.  Ollie makes another good point that his own experiences have helped to keep him alive this long without the use of superpowers.  Barry misses the point and thinks the former billionaire is experiencing jealousy for the first time, and throws his lack of super-abilities in his face.  Looks like Bivolo's powers are taking their toll after all, as Barry not only mouths off to Oliver, but his own Captain as well.  Making matters worse, Barry blows up at Joe, dredging up old history.

Now that the team is aware of Barry's mounting anger, they call in Arrow to help stop him (despite not having Cisco's cold gun any longer).  It might be a bit too late for Eddie, who is pulled out of a moving car by an enraged Flash.  Let's hope Arrow makes it in time!  (I mean, of course he does.)  There's a weird battle of pride between Diggle and Cisco about which hero will prove victorious.  Ollie's got plenty of trick arrows, but Barry's smart enough (and powerful enough) to counteract them.  Barry's anger is getting the best of him, just as he's getting the best of Arrow in a wild fight that tests Oliver's limits (and the creative team's stuntwork and visual effects).  Barry gets in a bruising barrage of fists, but Oliver is far from being beaten.  If it wasn't for The Flash's wicked healing ability, Ollie would have had him licked pretty quickly.  And if it wasn't for Wells and Joe showing up with a fun disco light show, Barry might very well have killed Ollie.

Well, so much for Chroma (or Prism, or the Rainbow Raider), since the team-up of Arrow and The Flash took him down off camera and put him in their own personal meta-human vault.  While the two teams are saying goodbye, Felicity gives Caitlin a sample from Canary's murder that will hopefully shed some light on the case.  Ollie's final parting shot to Barry is that it's never going to work out between him and Iris, so he should let it go.  He doesn't quite take this advice, but instead chooses to visit Iris in an attempt to explain his behavior from the night before, with little success.

Who is this random chick talking to Oliver, you ask?  Oh, just someone that Ollie used to know ... oh and perhaps the mother to Oliver Queen's lovechild?!

As we see Caitlin pining over a picture of Ronnie, we cut to two thugs picking on an apparent homeless man ... a homeless man who can conjure fire.  Two guesses who that is!

Okay, so while we get two pretty big fan moments to close the episode, tonight's hour was all about Barry's lack of focus as a burgeoning crimefighter.  It took quite a few nocks and knocks from Arrow to get the point across, that Barry's superpowers are an amazing gift, but one he must hone and perfect to become a truly heroic character.  I loved how Arrow's attention to detail and commitment to bettering himself through training clashed with Flash's carefree style and almost lazy attitude when it came to beating up baddies.  We'll see how they work together on Part 2 tomorrow night, and while I don't think we'll ever really see who would win in a fight between these two heroes, I'd love to hear your thoughts in the comments below!

Rating: A- 

Speeding Bullet Points:

• Eddie: "Your daddy hates tardiness."
• Say hello to Roy G. Bivolo, aka Chroma, played by Paul Anthony.
• Captain Singh: "My boyfriend has decided that we're going to eat healthy, so work is the only place I can eat what I like." What a weird way to let us know that the Captain is gay.  Did I miss something?
• Cisco: "A jedi craves not these things ... Anybody else feeling that quote?"
• Diggle: "I had a cousin who got hit by lightning once. He just developed a stutter."
• Well that's one way to get Felicity out of her clothes... Cisco: "I'll always remember this."

• 

  Diggle is weirdly obsessed with The Flash and it's hilarious.
• Oliver: "I'll help you catch bad guys." Barry: "Meta-humans." Oliver: "I am not calling them that." Barry: "Partners?" Oliver: "Partners."
• Oliver: "Barry, how can you have superspeed and still not be on time?"
• Oliver: "We can talk later about you giving your enemies code names." Barry: "Oh you mean over coffee with Deathstroke and the Huntress?"
• Caitlin: "You take too many risks. That's going to catch up with you." Barry: "Caitlin, I'm not Ronnie. You've got to stop treating me like I am."
• I love the revolving front door of S.T.A.R. Labs.  C'mon in, everybody!
• Honestly, introducing Chroma was a pretty interesting way to catalyze "Flash vs. Arrow", a battle that could have been much, much sillier.
• Oliver (on Wells): "There is something off about that guy."
• Eddie's new task force will make The Flash something of a vigilante in Central City.
• Oliver (to Barry): "Guys like us don't get the girl."