What do you do when you knew for a fact that you were supposed to die--and then didn't? That's the idea behind the CW's now-canceled Lucy Hale vehicle Life Sentence. It's also a big part of this week's episode of The Flash, the first back from the Crisis on Infinite Earths crossover. Everyone in Barry's life was preparing for an end, and that end never came. Now they have to deal with that. Roles are shifting and people are having to learn how to slow down. Spoilers follow for The Flash season 6, episode 10, "Marathon."

"Marathon"

The story this week is impressively unified along a single story thread of each of its main characters having to deal with Life After the Crisis. While these shows usually weave their stories together, the three plotlines this week are discrete stories of growth that will affect each other, but that are stronger because they're separate.

Before the Crisis, Barry left Cisco in charge of the team. Now that the Crisis is over, Cisco knows that villains from other Earths are now part of this one, including villains they may have already defeated. Cisco snaps at Nash Wells instead of dealing with his stress. He has regrets about giving up his Vibe powers because he thinks he could've saved people like Earth 2's Harry and Jesse.

Barry, meanwhile, receives a posthumous gift from Oliver. Diggle shows up to give Oliver the mask that Barry made for him back at the beginning of their arc. Barry thinks it has to be a clue about something, and that sends him on a wild goose that takes him and a very nauseated John Diggle all the way to Lian Yu.

Iris' tale is one that continues from before the Crisis. She's tracking the secret organization that employed Allegra's cousin and jumps the gun in doing so. She ends up facing off against a new variant of Dr. Light, who can charge up her rifle with her powers and use that to disintegrate whatever she hits. She misses Iris and gets a bunch of her evidence in the process. Iris goes to warn her contact, who Dr. Light disintegrates-before seriously injuring Iris in the process. Iris eventually realizes that she has to slow down and take a more careful approach to exposing a large corporation.

Cisco's storyline

Cisco isn't leaving The Flash, but he is taking a hiatus and word from the showrunners is that his return will bring back a major Flash villain. But what we get here are some great acting moments from Carlos Valdes. Cisco's guilt is overwhelming him. He's a true member of Team Flash here because he has himself convinced that he could've done more in a situation where the world literally ended.

Frost talks him down and helps him look at what he can actually do about his situation, and he realizes that he needs to actually take stock of the threats out in the world. This gives him a chance to make some peace and put Nash in charge of the tech side of things at Star Labs' We also learn that Allegra--or someone who looked like her on another earth--is someone important to him.

Barry's storyline

Barry, meanwhile, gets a visit from Star City's own John Diggle. Diggle has a gift for Barry: The mask that he gave Oliver. In Barry's mind, this is not a gift, but a clue. A clue that lets him hang onto Oliver's memory for a little longer and let himself believe that he's still in Crisis mode.

Barry studies the mask and finds Mirakuru on it, the substance that made Slade Wilson go insane and put together an army of Deathstroke terrorists. The discovery takes him and Diggle to Lian Yu, where they find that the Mirakuru is gone. John lays it out for Barry: the mask was a gift and nothing more. A reminder to Barry to live between the missions, not for the missions.

But the side effect of this is that it takes Barry a long way away from Iris.

Iris' storyline

Since the beginning of the season, Flash has been hinting at a secret society (not Leviathan, though). With Bloodwork and the Crisis out of the way, Iris zeroes in on this story and doggedly pursues it. She quickly makes an impressive amount of headway with the help of her burgeoning team of investigators.

Honestly, the idea of a news organization starting with no backing and finding success in 2020 seems less realistic than a man who can run at hundreds of miles per hour. But the storyline is giving Iris a more active role this year, and that's great.

Her pursuit of the story puts her in harms' way repeatedly; that Barry isn't there to save her ramps up the danger. There are no speedsters to casually put down their sandwich, put on their speedster outfit one leg at a time, and then run across town to pull her out of the path of a bullet.

Iris goes straight to the CEO of a corporation she thinks is involved with her unfounded allegations. That's not only very bad journalism, but it also puts Iris into the path of a bullet a second time. The team puts together a plan to stop Dr. Light and catch the CEO in his act all at once, and for once, their plan works. Iris gets the CEO and his assassin off of her back, protects her loved ones and ends up saving the day.

As she continues investigating, though, she ends up in the office of the corporation's former CEO, now missing. As she explores the office, she exposes a huge mirror. She turns around, away from the mirror, and in a pretty horrifying moment, a being comes out of the mirror and pulls her into it. Mirror Master returns, it seems.

Once more, with feeling (and VFX)

One thing the Crisis is doing is giving the Arrowverse lots of do-overs. The Arrowverse has had some excellent villains. Deathstroke, Reverse-Flash, and Alice all come to mind. But the Arrowverse has come together organically, and in the process they've missed the landing on quite a few villains, too. For every Reverse-Flash, there's a half-dozen or more Mirror Masters and Captain Boomerangs; villains that could be given interesting storylines but that were limited by the special effects capabilities of the show. Now, the show can re-visit these villains with better looking and more interesting abilities if they want to, and it seems like that's what they're doing here.

This episode is really well-put-together with a unified theme and three unique executions of that theme. It makes me excited to see what's to come for the rest of the season. A conspiracy theory about a secret organization isn't my favorite, but the tone feels good for the show, and it makes me hopeful about what's to come.