Oliver (Stephen Amell) and Deathstroke (Manu Bennett) square off in a battle of epic proportions in the first trailer for Arrow's Season 2 finale "Unthinkable", airing Wednesday, May 14th at 8 PM ET on The CW. Watch as Team Arrow clashes with Deathstroke's army in the streets of Starling City before this explosive season comes to a close next week.

Slade moves forward with his plan to kill one more person in Oliver's life. While Oliver has fought all year to be more than the killer he once was, when Slade kidnaps someone close to Oliver's heart, Oliver is pushed to the edge and realizes sometimes it takes doing the unthinkable to stop the monster. Meanwhile, Diggle takes on Amanda Waller (guest star Cynthia Addai-Robinson) with a little help from some friends, and Thea turns to Roy in her time of need.