- "He is committing suicide and he just invited the entire city to join him."
- —Oliver Queen realizes the danger from Sebastian Blood's Unity Rally
Oliver must tackle a new threat when bombs start to go off in Starling City. Felicity discovers the person setting them off is Mark Scheffer, a man who goes by the nickname Shrapnel. The Arrow discovers Shrapnel's next target is Sebastian Blood's "Unity Rally" and tries to talk the alderman out of hosting it, but he refuses. The Arrow sets off to stop the bombing, but Shrapnel tricks him and traps him in a bomb-laced antique store where he is unable to move without setting off the device. While Felicity helps Oliver, Diggle races to the plaza to find the bomb before it goes off. Meanwhile, Roy continues to hide his new strength from Thea but, after she witnesses his super strength in action at the rally, she demands answers. Laurel's suspicions about Sebastian grow stronger once she learns that he grew up with Cyrus Gold, the man who killed Quentin's partner. After Donner refuses to help her investigate, she turns to The Arrow for help.
Oliver continues his search for the man in the skull mask to no avail. Meanwhile, Felicity has been traveling to Central City to visit Barry who is in a coma due to the explosion. A serial bomber Mark Scheffer, who goes by the name "Shrapnel", begins setting off bombs across Starling City as an anti-government movement. Sebastian Blood begins his campaign as mayor, and decides to organize a Unity Rally for the city. Scheffer targets the rally, but Oliver is able to apprehend Scheffer, and the bombs disarmed. During the commotion, Thea witnesses Roy using his new strength and subsequently confronts him about it. Laurel continues to look into Blood, after discovering that he has ties to Cyrus Gold. She visits a mental institution, where she finds Blood's mother, who reveals that Sebastian killed his father and put her in the institution to cover it up. In a flashback, Slade experiences adverse effects to his mind and personality due to the Mirakuru.
- After the second bombing, when Officer Quentin Lance radios in, he gives his call-sign as "DC52"—an apparent reference to DC Comics' New 52 comics universe.
- The hospital where Sebastian Blood's mother, Maya Resik, is living, is named St. Walker's Hospital, a reference to the DC Comics character, Saint Walker.
- This is the first time Adam Donner, who was last seen in State v. Queen and seems to have fully recovered from his Vertigo overdose, has appeared.
- This episode revealed that Sebastian and Cyrus Gold had known each other years before the events of State v. Queen.
- Quentin Lance says that his arm injury still hurts when it's cold. This line was originally uttered by Bruce Wayne in The Dark Knight Returns.
Preparation ran from October 11 until October 22, 2013. Shooting ran from October 23 until November 1, 2013.
|"City of Heroes" • "Identity" • "Broken Dolls" • "Crucible" • "League of Assassins" • "Keep Your Enemies Closer" • "State v. Queen" • "The Scientist" • "Three Ghosts" • "Blast Radius" • "Blind Spot" • "Tremors" • "Heir to the Demon" • "Time of Death" • "The Promise" • "Suicide Squad" • "Birds of Prey" • "Deathstroke" • "The Man Under the Hood" • "Seeing Red" • "City of Blood" • "Streets of Fire" • "Unthinkable"|