Three Ghosts

"Three Ghosts" is the second Christmas episode of The CW series , originally aired as the ninth episode of the show's second season.

Synopsis
Barry manages to save Oliver's life. The former and Felicity are able to identify and locate Cyrus Gold. While continuing to investigate the death of Cindy's friend Max, Roy is captured by Cyrus and brought before Blood, who injects him with the serum, called Mirakuru, which kills Roy. Oliver arrives and kills Cyrus, simultaneously destroying the centrifuge and the remaining serum. The former revives Roy, but worries that the serum may affect him negatively. Slade is revealed to be alive in the present and the one orchestrating Blood's work; he orders Blood to leave the vigilante alone, so that he can deal with him personally. While Roy recovers at the Queen mansion, the serum injection heals the arrow wound in his leg. Barry leaves a domino mask for Oliver, to better hide his identity, and returns to Central City. While in his lab, Barry is hit by strange lightning created by an accident at the new particle accelerator lab. In flashbacks, Ivo kills Shado, but flees when Slade turns up with super-human strength and kills his men.

Availability
The episode was made available on the Arrow: The Complete Second Season DVD and Blu-ray sets, released by Warner Home Video on September 16, 2014.