The "Arrow" season 3, episode 9 spoilers reveal Ra's al Ghul threatening Oliver and the rest of Starling City over Sara's murder. Will "The Climb" finally unmask her killer?

It seems Oliver Queen will have his hands full once the leader of the assassins, considered to be the best at what he does, will descend upon Starling City to sow chaos.

The synopsis teased Arrow" season 3, episode 9 spoilers as it reads: "Nyssa (guest star Katrina Law) returns to Starling City and tells Oliver (Stephen Amell) that her father, Ra's al Ghul (guest star Matt Nable) has given Oliver 48 hours to find Sara's killer or the League of Assassins will start killing the citizens of Starling City."

Meanwhile, "Laurel (Katie Cassidy) is stunned when her father (Paul Blackthorne) delivers a very special Christmas gift - her mother, Dinah (guest star Alex Kingston). Meanwhile, Ray (Brandon Routh) tries to make amends with Felicity (Emily Bett Rickards) and Oliver sets a meeting with Ra's al Ghul."

This particular episode is directed by Thor Freudenthal and written by Jake Coburn and Keto Shimizu.

Roy Harper has been having vivid dreams about Sara Lance getting murdered. But the dream took turn for the worse when he realized that Sara died by his own hands.

Roy is not among the suspects in Sara's death, as it was generally attributed by the team to Malcolm Merlyn or one of the killers from the League of Assassins. But Merlyn already denied his involvement and even swore on Thea's life that he didn't kill Sara,w hich seemed to appease Oliver.

Meanwhile, Marc Guggenheim told Entertainment Weekly: "I've always maintained that you'd find out the answer to who murdered Sara by the end of the year. That said, I will say that the S.T.A.R. Labs team is going to end up providing a critical piece of information that cracks open the whole case, but that doesn't necessarily happen in [the crossover]."

Watch out for more "Arrow" season 3, episode 9 spoilers, which will be published ahead of the airing date on December 3 on CW.