Arrow: 10 Best Characters Who Only Appeared In One Episode
3. Nora Fries
As mentioned earlier, the Arrowverse's references to iconic DC lore only increased after the advent of the Flash, later seasons of the Flash, and Legends of Tomorrow. That said, it was an unexpected but entirely welcome surprise seeing Nora Fries (wife to Victor Fries) appear in the 2018 Elseworlds crossover.
Played by Cassandra Jean Amell (wife to Arrow star, Stephen Amell), Nora was placed in a cryostasis chamber by her husband after being diagnosed with MacGregor's Syndrome (an unexpected but interesting reference to the much-maligned Batman & Robin).
As she recovered in the chamber, she was experimented on by Dr. John Deegan, who had eventually grown to become the chief antagonist of the crossover. During the aforementioned Arkham breakout, she was released from her chamber, and in her delirium she sought out her husband's freeze gun to restore her body temperature to below zero.
She was able to escape in the chaos and possibly remained free till the multiverse was reset by the Spectre version of Oliver Queen. Though brief, it was a treat seeing a fan favourite such as Nora in the Arrowverse and possibly laid the groundwork for her iconic husband to appear later down the road.