Arrow: Extended Trailer For Next Week's Heir to the Demon Episode Reveals Big Secret

A long-standing theory here at ComicBook.com gets vindication in a new, extended trailer for Arrow's next episode, titled "Heir to the Demon." Just why have the League of Assassins been so hell-bent on bringing Sara Lance back into the fold? And how much does Oliver Queen already know about Ra's al Ghul and his family? We get some pretty clear answers in this extended preview, even though it's only an additional ten seconds over the trailer that aired last night after "Tremors" on The CW. You can check out the teaser below, and the official synopsis of the episode below that.

(8:00-9:00 p.m. ET) (Content Rating TBD) (HDTV) ALEX KINGSTON AND KATRINA LAW ("SPARTACUS") GUEST STAR — As Laurel (Katie Cassidy) continues to unravel, Oliver (Stephen Amell) and Lance (Paul Blackthorne) try to convince Sara (guest star Caity Lotz) to stay in Starling City and finally reunite with Laurel and Dinah (guest star Alex Kingston). However, Sara's fellow League of Assassins member, Nyssa (guest star Katrina Law, "Spartacus"), comes to bring Sara back to the fold, but when Sara refuses, Nyssa kidnaps Dinah. Realizing she's putting her family in danger by staying in town, Sara considers re-joining the league. Wendey Stanzler directed the episode written by Jake Coburn (#213).