As season four of "Arrow" rolls along, it looks like long-running adversary (and sometimes ally) Malcolm Merlyn (John Barrowman) will continue to make a nuisance of himself. In The CW's recently released plot synopsis for the April 6 edition of the show, titled "Eleven-Fifty-Nine," Merlyn looks to break this season's main antagonist, Damien Darhk (Neal McDonough), out of prison, along with further plot developments involving Laurel (Katie Cassidy), Felicity (Emily Bett Rickards) and Curtis (Echo Kellum). The full synopsis follows.

MALCOLM MAKES HIS MOVE - Oliver (Stephen Amell) and Diggle (David Ramsey) learn that Merlyn (John Barrowman) is going to try to break Darhk (guest star Neal McDonough) out of prison. Meanwhile, Laurel (Katie Cassidy) gets a surprising offer and Felicity (Emily Bett Rickards) has a heart-to-heart talk with Curtis (guest star Echo Kellum). Rob Hardy directed the episode written by Marc Guggenheim & Keto Shimizu (#418).

The "Eleven-Fifty-Nine" episode of "Arrow" airs 8 p.m. Wednesday, April 6 on The CW.