Fans finally get to find out who killed Sara Lance, a.k.a. Black Canary in a shocking new clip from the Arrow midseason finale "The Climb", airing Wednesday, December 10 at 8 PM ET on The CW. Bear in mind, this surprising revelation may be just a bit of misdirection to keep fans on their toes, since The CW likely won't spoil a massive plot twist like this in a clip one day before the episode airs. Still, it sets up an intriguing possibility for the finale, where Oliver is given just 48 hours to find Sara's killer by the nefarious Ra's al Ghul (Matt Nable), or else he'll start murdering innocent citizens of Starling City.

The clip also alludes to tonight's midseason finale of The Flash, where we see Felicity Smoak (Emily Bett Rickards) talking on the phone with Caitlin Snow (Danielle Panabaker). We also see a computer monitor that displays a news story about Reverse Flash's attack on S.T.A.R. Labs, although no major plot details are revealed for tonight's episode. It remains to be seen whether or not the characters from Arrow and The Flash will continue to be in communication with one another when their respective seasons return in 2015.

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Katrina Law also guest stars as Ra's al Ghul's daughter Nyssa, along with Brandon Routh as Ray Palmer and Alex Kingston as Dinah, Laurel Lance's (Katie Cassidy) mother in the final Arrow episode of 2014. Check out this new scene below before tuning in to the midseason finale on Wednesday night.