It's not all about crimefighting and superspeeding on The Flash; sometimes the title character gets to go on a date (well-timed for Valentine's Day, of course).  Barry's having a bit of trouble handling the heat, specifically the spicy food at the restaurant. (His first battle with the hot stuff doesn't go well.) His powers come in handy as he's able to rescue a little old lady and a suicidal building jumper rather easily without missing a beat during his date. Who says superheroes can't have it all? (Though superspeed isn't always the most desirable attribute when it comes to lovin', as Cisco makes quite clear.)

Meanwhile, at Concordance Research, Ronnie Raymond makes acquaintances with one Quentin Quale. This awkward conversation isn't exactly between Ronnie and Quale, but rather Firestorm's other half: Dr. Martin Stein. Firestorm has difficulty controlling his powers, and the so-called "Burning Man" ends up making another appearance on the daily news. The S.T.A.R. Labs team plans to go after Ronnie/Martin because he's becoming increasingly dangerous to the citizens of Central City. They start by paying a visit to Stein's wife, and showing her a photo of Ronnie to see if she recognizes him. It turns out that Ronnie/Martin have been watching Clarissa, so Caitlin and Dr. Wells hold a stakeout at the Stein house while Barry's on a date.

Though Barry's date goes very well, he has to stop prematurely when Firestorm shows up at the Stein house. The Flash arrives, ready to do battle, but Firestorm proves too hot to handle (I said it again!) the first time around. Firestorm takes The Flash for a ride across the city with Dr. Wells and Caitlin in pursuit. Round One goes to the Nuclear Man. Or so we think; turns out Barry placed a tracking device on Firestorm. The S.T.A.R. Labs team and Clarissa Stein find him under a city bridge, and though he’s certainly still out of it, he manages to control himself (themselves) long enough to ask for help.

Flashback!

Barry's riding a train and reading up on Dr. Wells' book, gushing over the particle accelerator that's about to turn on later that evening. He has a brief intellectual conversation with Dr. Martin Stein, who he doesn't know from Adam at the time. Later, Stein arrives too late (or just late enough) to see the accelerator turn on, and gets caught up in the blast along with his exposed Project F.I.R.E.S.T.O.R.M.

Later in the flashback, Ronnie stumbles out of an alley and snags a newspaper, showing him the accelerator's explosion on the cover. With Martin Stein in control, he makes his way back to his home, but obviously Martin's wife, Clarissa, doesn't recognize him, and calls the cops.

Stein's plan is to separate himself from Ronnie through nuclear fission. Ronnie, now all cleaned up and dosed up with drugs meant to treat dissociative identity disorders, meets up with the rest of the lab, though still speaking in the manner of Stein. While undergoing some tests, Stein tries to communicate what he believes Ronnie is thinking about when it comes to Caitlin. Things get a little heated, but could soon go nuclear if Wells' theory about separating the two entities proves correct.

In a bit of a strange pairing, Joe brings Cisco along on a case that takes them to the old Allen house in the hopes of finding out more on who killed Barry's mother. The house is currently occupied by a divorced woman who's, shall we say, eager to get to know Joe a little better. While she occasionally interrupts their investigation, Cisco discovers a mirror coated in silver nitrate that may have captured a photographic image of the night of Barry's mother's death. After a bit of tech-talk, Cisco reveals that he basically captured a three-dimensional stop-motion video of the night of the attack. Joe finds something in the still images: (shockingly bright and fresh) blood spatter from one of the speedsters at the crime scene. Now only time will tell just who the blood belongs to. Not much time apparently; Cisco pulls two separate blood samples, and is a bit shocked when Joe wants him to run them against Dr. Wells' DNA. Cisco defends his mentor, but Joe lays out his suspicions.

At the lab, Wells is proposing they kill Ronnie/Martin before Firestorm has a chance to go nuclear and wipe out the entire city. Poor timing on Wells' part as Cisco has just returned from his day with Joe in the field; the young scientist's own suspicions are rising. While Cisco is puzzling that out, Barry and Ronnie/Martin have another conversation in which the nuclear man convinces Barry that life's too short to miss out on opportunities, especially those involving pretty girls. Cut to Barry eating a "ghost pepper" to impress Linda; seems to do the trick.

Back to more important matters, Wells uses his stolen tachyon device and converts it into a "quantum splicer" which should hold Ronnie/Martin together. (Interesting that the villain (?) is using his speed device to save Firestorm, even if he's really just trying to save his own skin. All the more interesting considering that Wells' blood was not found at the Allen house.) Barry runs Caitlin out to meet up with Ronnie/Martin, who's about to kill himself to prevent nuclear disaster. After sharing a kiss (that was totally from Ronnie, right?), they attach the device to Firestorm's chest, but it doesn't appear to be working; Barry once again runs Caitlin to safety as Firestorm goes nuclear and they outrun the blast. Is this the last we'll see of the atomic hero?

Tonight's stinger (which was tough to focus on after that episode's closing stunner) features Clancy Brown as General Wade Eiling, who orders his team out to the site of the recent thermonuclear detonation in order to reclaim Project F.I.R.E.S.T.O.R.M.

"The Nuclear Man" certainly had a lot of heart, but for a show that prides itself on speed, this hour moved relatively slow to others we've seen. That's not really a knock on it, as it still speeds by the pacing of similarly plotted shows. It's just that tonight's episode definitely felt like the first half of a two-parter, which is exactly what it was. That being said, fans who have been clamoring for an answer to the show's use of time travel and for more on Wells' involvement with Barry's mother's death certainly got some meaty morsels tonight. Be sure to leave your latest theories in the comments below!

Rating: ★★★ Good — Proceed with cautious optimism.

(An explanation of our ratings system follows here.)

Miscellanea:

So how does a superhero get ready for a date? With superspeed and a barrage of costume changes, apparently.

Be sure to check out Christina's recent interview with Robbie Amell for more on his take on Firestorm and working with Victor Garber.

Barry: "If you're not sick of me by then, we can get FroYo."

As our own Allison Keene pointed out, "Cisco basically just made a 3D GIF from an antique mirror."

Dr. Wells: "I'm assuming you have Barry on speed dial."

Barry: "If you could just not ... flame on."

At this point in the love triangle, do you prefer Iris West or Linda Park? Or neither?

Wells: "It seems Ronnie's fight with the Flash has exacerbated the Firestorm matrix."

Anyone else catch Tom Cavanagh almost fly out of his wheelchair when he went down that ramp?

Martin/Ronnie: "Perhaps I'm now a lite beer man."

Wells: "Gideon, can the tachyon prototype be converted into a quantum splicer?"

For those of you who suspected that Future Barry was dueling with The Man in the Yellow Suit during the night of Mrs. Allen's death, it appears that you are correct.

General Eiling: "Bring me Firestorm."