'Arrow': "Spartan" Preview Released

Tonight on Arrow, the action centered around the ladies of Team Arrow with the Birds of Prey-inspired "Lost Canary", but next week the attention will shift to John Diggle as Ghostbusters veteran Ernie Hudson guest stars as a DIA General who has a history with him. What that history is? That's a bit of a mystery, but in a new promo for the upcoming episode "Spartan", it looks like things may go awry, putting Diggle in danger with the team having to spring into action to come to his aid.

In the promo, which you can check out in the video above, Diggle ends up the target in a mission gone wrong, something that puts him in a situation where it appears he -- and someone else -- are about to get tortured. All that we really know about the episode, other than this ominous scene, is that Diggle reaches out to the General for help -- and the vague language of the episode's synopsis has fans thinking that we may find out that this general is none other than Diggle's dad.

We know very little about Diggle's family, besides his late brother. Hudson was one of the two actors who played Burton Guster (Dule Hill)'s father on Psych, and fast-forward the decade since then, he would be roughly age-appropriate to do the same for Ramsey. Hudson appears in the upcoming Bad Boys tie-in LA's Finest with Gabrielle Union and Jessica Alba, and recurs on the Netflix series Grace and Frankie. He is best known for the role of Winston Zeddemore in the Ghostbusters films, and played the role of Bill, the uncle to Leslie Jones's Patty Tolan, in the recent Paul Feig reboot. Hudson, who has been the most vocal supporter of a Ghostbusters 3 over the years, is expected to return to the role in the upcoming film from director Jason Reitman. Hudson also recently played a high-ranking military official in Twin Peaks: The Return for Showtime.

On the Felicity side, the return of her old hacker friend Alena (Kacey Rohl) raises some interesting questions, particularly as the synopsis says that she has an "interesting proposal" for Felicity. That math adds up pretty quick when combined with the recent revelation that Emily Bett Rickards will be leaving the series at the end of season seven. Rickards has played Felicity Smoak on Arrow since the show debuted in 2012. Felicity's romantic relationship with leading man Oliver Queen (Stephen Amell) has been the focus of a passionate fanbase who ship the pairing as "Olicity." Given that the series is set to end after one more season, Rickards' decision to leave earlier than that may come as a surprise to some Arrow fans. She made the announcement with a poetic letter to fans on her Instagram account.

You can check out the official synopsis for the episode below.

ERNIE HUDSON ("GHOSTBUSTERS") GUEST STARS — After the Ninth Circle delivers a major setback for Team Arrow, Diggle (David Ramsey) reluctantly reaches out to a Four-Star General of the Defense Intelligence Agency (guest star Ernie Hudson) for help, despite unresolved tension from their past. Meanwhile, Oliver (Stephen Amell) discovers a piece of information that he believes will turn Emiko (Sea Shimooka) against the Ninth Circle. Alena (guest star Kacey Rohl) returns with an interesting proposal for Felicity (Emily Bett Rickards). Avi Youabian directed the episode written by Benjamin Raab & Deric A. Hughes.

Arrow airs on Monday nights at 9 p.m. ET/PT, following episodes of DC's Legends of Tomorrow on The CW. "Spartan" will debut on April 22.