: The episode concludes with a striking cliffhanger: Iris is pulled into a mirror by silver arms, signaling the arrival of a new iteration of Mirror Master. Visuals & Tone
“"Marathon" deals with the fallout of Crisis while setting up the second half of the season... it manages to be more gripping and heartfelt than that boring, anticlimactic waste of a crossover was.” Geeks + Gamers · 6 years ago [S6E10] Marathon
: Iris pursues the secret organization "Black Hole," which has been using metahumans as assassins. This storyline grounds the season’s second half in a more grounded, noir-inspired mystery. : The episode concludes with a striking cliffhanger: