The CW has released the official synopsis for “Restoration,” the forthcoming third episode of Arrow’s fourth season.

“Restoration” — (8:00-9:00 p.m. ET) (TV-14, LV) (HDTV)

LAUREL TAKES HER SISTER TO NANDA PARBAT — The growing tension between Oliver (Stephen Amell) and Diggle (David Ramsey) puts both their lives at risk when they go after Damien Darhk (guest star Neal McDonough) and a H.I.V.E. deployed meta-human. Meanwhile, Laurel (Katie Cassidy) talks Thea (Willa Holland) into returning to Nanda Parbat to ask her father (John Barrowman) to put Sara (guest star Caity Lotz) into the Lazarus Pit. However, Laurel is surprised when Nyssa (guest star Katrina Law) refuses to do it. Wendey Stanzler directed the episode written by Wendy Mericle & Speed Weed (#403).

Original airdate 10/21/2015.