WARNING: This article contains major spoilers for The Flash season 6 episode 10. Read at your own risk.
The Flash season 6 episode 10 aired on Tuesday night, Feb. 4, on The CW, with the title "Marathon." The episode serves as the midseason premiere and shows how the remaining heroes cope with their lives after the Crisis on Infinite Earths crossover events.
In The Flash season 6 episode 10, Iris, Cecile, Kamilla, and Allegra -- or the Team Citizen -- investigate the mysterious secret organization; Black Hole. Iris met with an anonymous source, who claims the organization is connected to McCulloch Technologies, but CEO Joseph Carver denies the allegations.
However, Iris published her story, causing McCulloch to sue the Citizen for defamation. Iris's life is in danger after that, with the Black Hole orders to kill her. Meanwhile, Dr. Kimiyo Hoshi is a metahuman who can control light and a dangerous Doctor Light in the post-Crisis world.
He tried to kill Iris several times in The Flash season 6 episode 10. She managed to escape her second encounter with him, but her source, however, has been murdered. Iris became more determined to take down the Black Hole because she hasn't still disengaged from Crisis.
But Joe reminds her she doesn't have to live like that since they already survived the event. Iris soon realized she needs to have a strategic plan to take down the Black Hole. Frost and Joe set up a trap for Doctor Light, while Iris confronts Joseph Carver about being the Black Hole's leader.
She threatened the CEO and said she'll release all the information she has about him and the Black Hole if they harm her or her friends. Carver then called off Doctor Light and dropped the defamation suit as well. However, Iris still sneaks into the McCulloch Technologies to find information about his wife.
Carver's wife, Eva McCulloch, is missing and her disappearance might be connected to the Black Hole. Iris thinks she may find some clues in Eva's abandoned McCulloch Technologies office. She sneaks into the abandoned office, and there, she discovered a giant mirror.
Two silver hands suddenly emerged from the mirror and pulled Iris inside of it. The question now is: who pulled Iris? Some speculated those were Eva's hands, and she might be the new version of Mirror Master; an Iconic villain in The Flash.
Meanwhile, The Flash season 6 episode 10 also sees Bary coping with life and Oliver's death. Diggle gave him a gift from Oliver; the mask Barry made for him during the early run of Arrow. Barry then noticed the mask has traces of Mirakuru and believed Oliver left it to warn him about a new threat.
So, Barry dragged Diggle to Lian-Yu, but there's no trace of Mirakuru out there. But then, Diggle helped him realize the real meaning of Oliver's sacrifice; there's more to life. He told Barry that Oliver didn't want him to go down the same path as life is more than just the mission.