Taken

"Taken" is the fifteenth episode of the fourth season of Arrow and the eighty-fourth episode overall. It aired on February 24, 2016.

Synopsis
Oliver realizes he needs help battling Damien so he calls in an old friend – Vixen. Using her magical ability to summon animal powers, Vixen gets a lock on Damien's location and the team goes to war. Meanwhile, Thea has a heart-to-heart talk with Malcolm.

Production
Preparation ran from December 17, 2015 until January 8, 2016. Shooting began on January 11 and ran until January 20, 2016.

Trivia

 * John Constantine is mentioned to be literally in Hell.
 * This episode marks the first live action appearance of Mari McCabe since her animated appearance on Vixen. Megalyn Echikunwoke voiced the character and reprise the role.
 * Oliver notes that his last encounter with Mari was "animated", a tongue-in-cheek reference to the duality of their previously heated encounter and the fact that the web series Vixen was literally an animated series.
 * In the comics, Vixen was originally introduced as an enemy to Superman before going on to become a member of Justice League Detroit.