As Barry and Joe reopen the investigation into Nora Allen's murder, a number of gangsters are killed mysteriously. With all the signs pointing to a metahuman being responsible, it will fall to the brilliant team at STAR Labs to construct a prison capable of holding super-powered criminals. This requires reopening their old particle accelerator and reopening some old wounds. And as Caitlin Snow struggles with memories of the fiancee who died a hero's death saving Central City, Barry will struggle with a murderous man made of living toxic gas.
The Flash: Rebirth (the background with Barry's mother being killed and his father framed for the murder), The Golden Age Starman comics of Gardner Fox (The Mist) and the Sam Raimi Spider-Man films (Barry's opening and closing narration)
Danielle Panabaker proves to be far less cool in this episode than in previous outings as Caitlin Snow. We get to see the character warm up a little in the flashbacks and her character in the present is given further development as we see why she has been so reluctant to let Barry run off into danger.
There's some nice artistic design - to save nothing of situation-based irony - in the locations where The Mist attacks his victims. All of the locations are sealed behind glass (the front room of a restaurant, a mall elevator and the visitor's room of a prison) and resemble, in some fashion, a gas chamber.
When accused by Joe of saving people just for the glory, Barry says that he doesn't expect people to build a museum in his name. In the comics, this is exactly what the people of Central City did to honor him in The Flash #154 (August 1965).
Joe West notes that Iron Heights isn't equipped to handle metahumans. This is ironic, as the original Iron Heights prison from The Flash comics was a prison specifically built to handle super-powered criminals.
The flashbacks for this episode give us our first glimpse of Caitlin Snow's fiancee, Ronnie Raymond. In the comics, Ronnie Raymond was one of the two men (the other being scientist Martin Stein) who united to become the superhero Firestorm after both were caught in an accident at a nuclear power plant.
Before the particle accelerator is activated, Harrison Wells says he feels like he's been waiting for this day for centuries. This may be a bit of foreshadowing given some of the fan theories of Wells being a time-traveler from the future.
In the original police interview regarding his wife's murder, Dr. Henry Allen explains that his wife was stabbed to death and that the reason that his fingerprints were on the murder weapon were because he had to stabilize the knife while trying to treat her wounds.
Ronnie Raymond's given occupation here is structural engineer. He was responsible for putting together STAR Labs' particle accelerator. In the original comics, Ronnie Raymond was a high school student with little inclination toward science or school work in general.
Caitlin says that Ronnie compared the two of them to fire and ice. This is a reference to their code names from the comics - Firestorm and Killer Frost.
The Central City Mall has a Big Belly Burger. DC Comics fans will recognize this as the name of a popular fast-food franchise from the DC Universe. Arrow fans may recognize it as the name of the restaurant that Diggle's sister-in-law ran in Starling City.
In the comics, airborne poisons are one of the few effective ways to neutralize The Flash. He still needs to breathe oxygen like a normal person and his hyperactive metabolism will circulate the poison around his body faster than normal.
In another nod to the comics, Caitlin notes that she can't give any anesthetic to Barry when they perform surgery on him since his hyperactive metabolism will burn through anything they inject into him before it can affect him.
The Mist's real name in this episode is Kyle Nimbus.
The word nimbus means "dark cloud".
In the original DC Comics, The Mist was the arch-enemy of the Golden Age superhero Starman. His real name was never given in the original Golden Age comics. The 1990s Starman series gave him the first name Kyle but no last name.
This version of The Mist was a hitman before he gained superpowers. The original Mist was a soldier and a scientist.
This version of The Mist transforms into a poisonous gas - Hydrogen Cyanide. The original version of The Mist transformed into an unidentified narcotic gas that allowed him to put people to sleep or - in some stories - a suggestible hypnotic state.
When Barry sees his father in the visiting room at Iron Heights, he vibrates his face at super-speed, causing it to blur from his father's perspective. This was a frequent trick used by The Flash in the comics when Barry Allen had to either operate without his costume or work in close proximity to someone who might recognize him as Barry Allen.
Caitlin has a fondness for ice cream.
According to Henry Allen, Barry was a late bloomer, being the last child of his age to learn how to walk. When he took his first steps, he ran straight to his mother.
We see Iris' blog on The Flash - "The Streak Lives".
Harrison Wells had some kind of pre-knowledge of what would happen to Barry Allen, and was watching him through a camera in his secret room on the night of the particle accelerator explosion.
In the Police Code used in Central City, a 237 is Public Indecency. A 239 is a Dog Leash Violation.
Barry notes that the men killed in the restaurant showed signs of hypoxic asphyxia, consistent with exposure to poison gas.
The Mist's attacks do not leave poisonous gas residue behind but they do leave behind traces of his DNA.
The Mist turns into a mixture of hydrogen cyanide and a sedative. Hydrogen cyanide is one of the chemicals used in American states where the gas chamber is used for administering the death penalty.
The cell containing The Mist is powered by an 8.3 tesla superconducting magnet. This is approximately 100,000 times the strength of Earth's magnetic field.
Barry: It doesn't matter if you're the slowest kid in gym class or the Fastest Man Alive - every one of us is running. Being alive means running. Running from something. Running to something. Or someone. And no matter how fast you are, some things you can't outrun. Some things always manage to catch up to you.
Harrison: Now that we have a sample, we'll get to work analyzing it. Figure out the make-up of the poison. Maybe get a clue as to his human identity.
Cisco: Or a least a way to stop him from turning into g a mist.... The Mist! Okay! That's his name. End of discussion.
Joe: I have been a cop for almost as long as you've been alive. So you should know putting on that suit does not make everybody safe. For every person you save, there's going to be somebody you can't. And the hardest thing you're going to have to face is not some monster out there with powers. It's going to be that feeling of uselessness when you can't do anything. Or the guilt that weighs on you when you make a mistake. Some things, Barry, you can't fight. Some things you just have to live with.
Caitlin: He saved so many lives that day. And no one will ever know what he did.
Barry: I do. He was a hero.
Caitlin: I didn't want him to be a hero. I wanted him to be my husband.
(As Barry wakes up in a chair while watching Joe in his hospital room)
Joe: Been a while since I watched you sleep.
Barry: Rescuing you is exhausting.
Joe: (chuckling) I really miss the ability to be able to ground you.
Barry: Sorry I went and grew up.
Iris: Dad, the thing is -
Joe: - you two are dating. I know.
Iris: You do?
Joe: I am a detective, remember? And both of you are lousy liars.
Eddie; So you're not mad?
Joe: Oh, I'm mad. If the doctor hadn't confiscated my gun, we'd be having an entirely different conversation.
Barry: I thought being The Fastest Man Alive would make my life easier. That I could outrun anything. Turns out no one can outrun pain. Life is tragic. But it's also precious. And sweet. And extraordinary. And the only way I know to honor my mom's life is to keep running.
We see clips from F101, depicting the press conference before the STAR Labs particle accelerator was activated.
The Boomerang Factor
The Mist must have some form of defensive reflex to be able to shift into a gaseous form faster than The Flash can move in to punch him.
The Bottom Line
A solid episode that gives Caitlin Snow some much needed character development and even gives comic-relief Cisco Ramon a chance to show some depth. Comics fans may quibble about some of the changes made to the characters of The Mist and Ronnie Raymond but they prove largely to the benefit of the story, with The Mist being upgraded to become a truly effective menace to The Flash and Ronnie Raymond becoming an earnest and heroic young man compared to his goof-off comic book counterpart. The only real weak spot is the on-going romance between Eddie Thawne and Iris West, but it's worth suffering through for the brilliant pay off of Joe's response.