Is there a Dark Horse in the Palace? (Spoilers)

The term “Dark Horse” has many definitions, including: “a person who reveals little about himself or herself or his or her activities, esp one who has unexpected talents or abilities.”  I believe Chief Royal Guard Kim Hwan is a  “dark horse” who is at least indirectly subverting the King and protecting “the Watchman” and, perhaps, the identity of Leo Seol (Kang San)

When I began to watch this drama (just one short week ago!), I kept a lookout for one actor:  Joo Seok Tae who played Woo Tak in Alchemy of Sous.  In Guesthouse, his role is Kim Hwan, Captain of the Royal Guards and the “only person Lee Chang (King) believes in [trusts].”

For most of the drama, Kim Hwan stood around, observed, said little (and killed a few innocents ☹), but there were some key scenes (see below).  However,  Episode 12 convinced me that Kim Hwan is no longer 100% loyal to the King.

Protecting the Watchman/WatchMEN(?).

Ep. 3: Kim Hwan tells Left State Minister that (i) the Royal Guards do not know anything about the WatchMEN; (ii) training has been done in secret for generations; (iii) the Queen Mother funds them from Royal Family funds, but she doesn’t know any details.  He then warns Left State Minister:  “I beseech you – do not look for them.  If you  push them into the light, you might not be safe either, Left State Minister”

Ep. 10 (Mark 41): As Tae-hwa and King discuss Dan-Oh and Lee Seol, Kim Hwan pays special attention when the Watchman is mentioned.  

Protecting Identity of Lee Seol - OR keeping an eye on a potential traitor?:

Ep. 9 (Mark 31) As the King remarks that San’s eyes look familiar, Kim Hwan notices that Kang San is gripping his sword.  Rather than drawing attention to that, Kim Hwan says San is “insolent and should lower his eyes.”

 At the Royal Guard initiation, Kim Whan carefully notes that Kang San is capable of drinking large amount of alcohol.

Ep.  10 Kim Hwan watches carefully as the King and Kang San fight with swords. 

EPISODE 12 – Seals the Deal that Kim Hwan is capable of subverting (or not being 100% loyal) the King.

• Kim Hwan has taken the “goofy” Royal Guard (Yoon Gu-nam) under his wing.  Is it because he knows he is incompetent (thereby protecting Lee Seol and the Watchman).  Or, is it because (unlikely) Gu-nam is another Watchman?
• The Watchman escaped easily when the Kim Hwan and Goofy were chasing him.  I don’t believe Kim Hwan cared if they caught him or not.  
•  Kim Hwan leads the guards to the Fabric Merchant looking for Kim Chi Woon, the bodyguard of former Crown Prince Lee Pyeong.  Kim Chi Woon looks directly at Kim Hwan and nods his head slightly before running away.  Kim Hwan – who was part of the coup – would have known and recognized Kim Chi Woon.  Furthermore, it was Goofy that tried to scale the wall (and failed)
• Kim Hwan tells the King that all records related to Lee Pyeong’s bodyguard were burned.  He (or some of his guardsmen) are now on their way to Gaeseong to collect more information on Kim Chi Woon. 
• Kim Hwan sends Goofy to the Guesthouse and told to “guard Dan-oh”.  – supposedly from the Watchman
  

FINAL NOTE:  On two separate occasions each year, the King is guarded only by the Chief Royal Guard Kim Hwan.  Kang San is planning his attack at the next occasion:  New Years Eve (late January/early February) or the 15^th Day Of June (ritual for the God of Agriculture). 

I totally agree with you 💯 usually background characters aren’t really given any screen time but he was, which makes him a non background character. The way he does things makes him suspicious indeed and I believe that he is the watchman from 8 years ago. Wouldn’t it be so cool if we see Chief Inspector Jang vs Chief Guard Kim Hwan! It would be a spicy fight lol I hope it happens. This will also increase Shi Yoel’s luck with Hong Ju’

Ps. I love reading detailed posts like these 

 XianKK:

I think episode 14 will reverse your thoughts again... 😁 

I don't know if it "reversed" my thoughts, but it appears that Royal Guard's close focus on Kang San in past episodes was Option 2:  "keeping an eye on a potential traitor".

I wrote my original topic before Ep. 13 - and I'm even more inclined to believe that Chief Royal Guard was once the "Watchman" for the prince Lee Chang (who, I believe, was actually a Third brother since the Dowager Queen stated she already lost 2 sons - presumably the original Crown Prince and also the "Grand Prince" we have heard about occasionally in this drama).

Chief Royal Guard's job is to protect the PHYSICAL safety of his "master" - but it isn't necessarily to protect his status or position vis-a-vis the "throne".   He is not interested in politics according to tvN character description. 

There is more to his story.  And I believe it is related to "the Watchmen" group.