‘Reign’ Season 4, Episode 13 Spoilers, Promo Revealed: John Knox And Darnley Team Up To Overthrow Mary In ‘Coup de Grace’

"Reign" Season 4, Episode 13 features power play and death of Mary's loved one. The upcoming segment is titled "Coup de Grace" wherein Darnley and John Knox team up against Mary. Read for further details.

[Spoiler alert! This article contains spoilers for "Reign" Season 7, Episode 13 "Coup de Grace." Do not read further if you don't wish to know more about it.]

Mary has another challenge to deal with as Darnley and John Knox join hands to overthrow Mary and snatch her throne. According to the description of "Reign" Season 7, Episode 13, John Knox and Darnley pull up a coup against her. Unfortunately, Mary's close friend becomes a victim of their plan and bites the dust.

Elsewhere, Elizabeth is forced to make a tough decision. Her future husband asks her to banish Gideon from the king the court. Meanwhile, Charles stands up against his brother Henri.

"IT'S HUSBAND AGAINST WIFE AS DARNLEY WORKS TO RUIN MARY - Darnley (Will Kemp) teams up with John Knox (Jonathan Goad) to strip Mary (Adelaide Kane) of her throne, which will leave a close friend of Mary's dead. Elizabeth (Rachel Skarsten) must banish Gideon (Ben Geurens) from court at the request of her future husband (guest star Steve Byers), while Charles (Spencer MacPherson) takes a bold stance against his brother Henri (guest star Nick Slater)," reads the official synopsis for "Reign" Season 4, Episode 13 as on Spoiler TV. The episode titled "Coup de Grace" was written by John J. Sakmar and Kerry Lenhart and directed by Megan Follows.

A promo video for "Reign" Season 4, Episode 13 is highly anticipated. It is expected to be released after the conclusion of episode 12 airing on May 12. Stay tuned, it will be updated here.

"Reign" Season 4, Episode 13 airs May 19 at 9:00 p.m. ET on The CW. Spoilers and updates are expected soon.