Team Arrow has a plan to infiltrate the Ark and rescue Thea from the clutches of her father, Malcolm Merlyn. Of course, with Damien Darhk involved, and the Calculator helping Oliver, Diggle and his daughter, Felicity, with their mission, it's probably not a surprise to learn that things are going to go sideways.
The penultimate episode in "Arrow's" fourth season,"Into the Flood," airs Wednesday, May 18 on The CW.
"Lost in the Flood" -- OLIVER FIGHTS FOR THEA; DONNA SMOAK FACES OFF WITH NOAH KUTTLER -- Following the shocking events in the previous episode, Oliver (Stephen Amell) and Diggle (David Ramsey) race to rescue Thea (Willa Holland), while Felicity (Emily Bett Rickards), Curtis (Echo Kellum) and Noah (guest star Tom Amandes) join together to stop Darhk (guest star Neal McDonough).
Starring Stephen Amell and Emily Bett Rickards and David Ramsey, "Arrow" airs Wednesdays at 8 pm EST on The CW.