A gaseous meta-human murderer is on a vengeful rampage while Barry struggles with his revived feelings of helplessness in regards to his father’s imprisonment and his mother’s murder. Star Labs converts the particle accelerator into a prison for meta-humans while Alison struggles to come to terms with her fiance’s death inside that very structure. Meanwhile, Eddie and Iris must figure out how to tell Joe that they’re dating.

The Chase

A meeting of mob bosses is taken down in seconds by a green swirling cloud. When the police investigate and there’s no sign of a deployment vehicle for the deadly gas, Barry has an idea that they’re dealing with a meta-human who can manipulate gases. That theory changes slightly when Barry takes a sample of the gas from one of the victims and instead of finding a toxin finds another person’s DNA. The meta-human doesn’t control gas, he is gas. The Mist, as Cisco aptly names him, goes on to attack a judge who’s out shopping at the mall. She recognizes him immediately, saying that he’s supposed to be dead. He turns into gas and poisons her.

When Barry arrives on the scene as The Flash, he tracks the Mist and confronts him in private. The Mist attacks him and Barry runs back to Star Labs, barely able to breath, but with the poison in his lungs for his friends to analyze. His regenerative powers allow him to survive the attack. The toxin is a cyanide gas mixed with a sedative, a mixture used on death row prisoners. It turns out there was a man named Kyle Nimbus (Haha, because nimbus is a cloud and he’s gaseous) being executed the night of the explosion. He’s on a murderous rampage of everyone who had a hand in his conviction and execution, which ultimately includes Joe, the investigating detective.

Joe makes a visit to Barry’s father to apologize for not believing in him, and to tell him that he’s reopening the case on his wife’s death. Henry is a pretty understanding man and seems to hold no malice toward Joe, especially since he raised his son. The Mist comes to the prison to attack Joe. Barry arrives shortly afterwards with an antidote to the poison, saving Joe’s life. Henry looks on at amazement, first at the man who can turn into a swirling cloud of gas, and then at the red streak who comes to save the day.

Barry goes after the Mist, provoking him and then leading him on a long chase to tire him out. It is Wells’ theory that because gas is the most unstable form of matter, that Nimbus will have to come back to his solid form to rest. He does and Barry is able to knock him out and imprison him in the particle accelerator.

Caitlin and Ronnie

No one has been down to the particle accelerator since the explosion nine months ago, and to Caitlin, that means facing the death of her fiancé, Ronnie Raymond (there’s a meta-human name if ever I’ve heard one). While it seems pretty likely that Ronnie isn’t actually dead and that he’s probably now one of the numerous meta-humans roaming Central City – just an unfounded theory – it’s obviously still an issue for those who believe he died that night. Barry and Caitlin bond over their respective losses. He eventually accompanies her to the particle accelerator, where she faces the trauma of that night and comes to terms with what Ronnie did to save the city.

Eddie and Iris

Eddie is sick of sneaking around with Iris and lying to his partner. He wants to tell Joe the truth about his relationship with Iris, but Iris is hesitant. When it seems likely that she could lose Eddie if she doesn’t get serious, she decides to come clean. Of course, Joe knew the whole time that Eddie and Iris were seeing each other – he’s a detective, remember? – but is still kind of mad about it. He doesn’t like complications, and his life has gotten complicated enough in the last few weeks. Since Iris really likes Eddie, Joe promises to try his damnedest not to shoot him. Barry, of course, plays the role of the supportive friend, as always.

Barry and Joe

Joe reopens the investigation into Nora Allen’s death and promises to work with Barry to get his father released from prison. Barry struggles with his conscience, wanting to break his father out of prison instead of waiting. Joe reasons that Henry wouldn’t want that. Without evidence and an official release, Henry would be on the run, and what kind of life would that be? Joe says that there are some things you can’t run away from, and that’s the pain of losing a loved one, or the guilt when you make a mistake, or the feeling of helplessness when there’s nothing you can do to save someone. Barry feels like he should be fast enough to save everyone, that he should have been faster to save the judge at the mall, but it really comes down to his helplessness to save his mother or to exonerate his father.

Harrison Wells

While Jesse L. Martin is probably the best part of the show, Tom Cavanagh as Harrison Wells is a close second. There’s something about the way he speaks that’s slightly odd and vaguely compelling, and the dynamic between his beneficent exterior and his dark, secret life is fascinating. There are all sorts of theories flying around about who Wells really is – especially since he has no named counterpart in the comics – and it’s pretty likely that “Harrison Wells” is just a cover for who he really is. Like John Harrison and Khan in Star Trek Into Darkness. Is he the Reverse Flash? Is he Barry from the future? Why does he pretend to be crippled?

It is implied during flashbacks of the night of the explosion, as Wells watches a live feed from Barry’s lab of the circumstances that would give him his abilities, that Wells had foreknowledge of The Flash and that he potentially engineered the events that created him. Did Wells sabotage the particle accelerator in order to create The Flash? And what exactly does he mean when he says he feels like he’s been waiting for this moment for “centuries”? In the world of comics, you get to take every metaphor literally. He clearly has access to information from the future, and combined with this comment, he could potentially actually be from the future. There will probably be a big reveal by the end of the season, but for now all we can do is collect the clues and build our theories.