The Flash returned for Season 4 last night, and things already seem to be moving at a breakneck pace. But between Barry's return and The Thinker's reveal, there were some details that fans may have missed, or misunderstood, that could mean quite a lot in regards to how the rest of Season 4 takes shape. On the flip side, they could also mean absolutely nothing, as we're still early in the season. But it never hurts to speculate, so here are some noteworthy moments that may or may not be worth keeping in mind as the show moves forward.
This House Is Bitchin'
Barry returned from the Speed Force in a confused state and started going full-on John Nash as he littered any and all walls with symbols that Cisco eventually translated to "This House Is Bitchin'." The line meant absolutely nothing to Barry when he snapped back to reality, which itself is understandable, but isn't it weird he didn't even remember it (or anything else from his fugue state)? Wally and Jay have spent extended periods in the speed force, and neither one came out with pre-packaged memory loss. That Barry remembers nothing of when he was acting crazy potentially nixes Cisco's belief that Barry was attempting to send a secret message to the team.
Was this really the work of the Speed Force, though, or is it possible Barry's brain fuzz was brought on by something or someone else? We're skeptical about everything, given The Flash's villain in Season 4 is a known telepath, but it's completely plausible Barry's personality lapse was just related to the speed force and nothing more. Not likely, but plausible.
The episode may have been titled "The Flash Reborn," but it was jam-packed with references to Season 1. The airline strip and Lady Gaga's "Poker Face" were both featured in the pilot episode, as were several different lines of dialogue, and Peek-a-Boo made her return for the first time since her escape in Episode 22. Despite all the nostalgia, however, nothing brought Barry back to normal until Joe said, "Iris is going to die," which set the Scarlet Speedster back into action.
Barry doesn't speak again until Samuroid says, "Flash, Welcome Home," and then he's seemingly back to normal. Assuming specific keywords knocked The Flash out of his state, the saving Iris trigger is an obvious callback to Season 3, but what about "Welcome home?" Perhaps the line was a callback to the premiere of Season 2, where the character ensemble had a "welcome home" party for Barry's father Henry upon his release from prison. Did remembering a huge moment from his past trigger Barry to return back to normal? That might come in handy should something like this happen again, but was it just happenstance or was it planned that way?
That Diapers Line
Barry is spouting all sorts of gibberish and rhymes when he bursts back into Central City, but one line in particular has The Flash fans excited. "We're gonna need more diapers," was a surprisingly coherent moment for the speedster, offering up his first big smile in the episode, and many comic fans started wondering if Barry had seen his future inside the Speed Force. Could it be that Barry and Iris West will one day be expecting not just one child, but twins?
"More diapers," either implies a very poopy kid or (more likely ) more than one kiddo, and considering the couple currently have none, Iris could soon be pregnant with twins! Specifically, she could be pregnant with the future Tornado Twins Don and Dawn West, who boast the same super abilities of their father in the comics. It would be an interesting spin if that line actually referred to Jai and Iris West II, the more recent iteration of the Tornado Twins that were the offspring of Wally West and Linda Park. Maybe Barry's worried about other people's diapers.
Catilin's "Inner Struggle"
When we last left Caitlin Snow, we assumed she had made peace with her split personality Killer Frost and was now in control of her abilities. We had no reason to feel any differently throughout a bulk of the premiere, until some later moments when she tried to freeze a dude's head off after a bar scuffle. After a brief mental struggle, Caitlin seemed to be back in control as the scientist we all know and love, but how difficult is it for her to handle?
That will be an interesting question to answer as Season 4 of The Flash continues, since we now know that Caitlin is/was secretly working for Amunet Black. Known as Blacksmith in the comics, Black is not a good person, which has us wondering whether or not Caitlin or Killer Frost is really in control of the character's life. It could possibly even be both, which might cause some issues with Team Flash later this season.
The Samurai Android
When we learned Samuroid was just a tool tasked by The Thinker, didn't every fan of The Flash go back and rethink this whole episode? If not, consider this: Team Flash went six months without Barry, and 24 hours after the Samuroid showed up, our quick-footed hero is back home and being beckoned by his digital aggressor. It makes us wonder who is really pulling the strings here!
Why would a mentally powerful villain encourage a superhero to return when an entire city is up for grabs? Perhaps The Thinker's beef is with Barry Allen specifically, which would make sense if it weren't for the fact this is supposedly the first time we've seen this guy in the series. If The Thinker is someone from the future, that would be more sensible, and it would certainly make manipulating people easier if he knew what was going to happen already. But why is it happening?