"Fundamentals" is the eighteenth episode of the sixth season of Arrow, and the one-hundred-thirty-third episode overall. It aired on April 12, 2018.


In his darkest place yet, Oliver wonders if he has failed at everything – being a father, a mayor and a hero. His frustration rising, Oliver lashes out at Felicity and William. A surprising visit from an old friend has Oliver questioning his next move.[1]




  • "Back to the Basics" was the original title for this episode.[2]
    • Near the end of the episode, Oliver says that he needs to go "back to the basics," likely indicating the title change was a post-shooting decision.
  • Felicity mentions that she "Parent Trapped" John and Oliver, referencing a scene from 1961 film The Parent Trap in which the protagonists trick their separated parents into seeing each other.
  • Josh Segarra and Kirk Acevedo previously appeared on Blue Bloods.


  1. Arrow #6.18 Description: “Fundamentals” - GreenArrowTV
  2. Arrow - Episodes 6.17 & 6.18 - Titles Revealed - SpoilerTV