Duan Huai Yi - beloved, long-lost brother or ...?

The Public Prosecutor’s Office vs. Duan Huai Yi

Charges:
The defendant, Duan Huai Yi, stands accused of murder in the first degree, having allegedly conspired with one or more ministers of the North Ji court to poison Duan Zi Ang, Emperor of North Ji.

Exhibit A: The Poison

The mystery of Zi Ang’s “illness” has never sat right with me.
The only explanation we’re given comes from Huai Yi himself, who tells Shu He:

“The Red Shadow Guards’ diet has been controlled since childhood. I read the records — all their chiefs died in their prime.”

But this doesn’t hold up under scrutiny.

For one, we see the former Chief of the Red Shadow Guards — Zi Ang’s uncle — alive and well in his fifties, clearly past his prime and in good health. That alone undermines this claim.

If every chief truly died young, wouldn’t that be common knowledge within the organization? Who would willingly accept a post that guarantees an early death? Such a pattern would be impossible to hide — and even harder to justify.

Furthermore, the position of Chief is said to be held exclusively by members of the royal family — typically younger sons of the emperor. It makes little sense to deliberately poison imperial blood, especially potential successors. While one might argue that eliminating rivals serves a political purpose, systematically killing royal sons would be far too dangerous and politically short-sighted.

My theory: Huai Yi (or a faction within the North Ji court) began slowly poisoning Zi Ang as he rose in power.
Zi Ang may have unified the kingdoms, but he did so by killing his own father — a deed that surely left many in court harboring deep resentment. 

Exhibit B: Language and Identity

When Huai Yi is first introduced, he refers to his long-lost brother as 兄长 (xiongzhang) while speaking to the abbot:

“My family was massacred, and I was separated from my elder brother.”

Later, Zi Ang remarks:

“When my brother was young, he never called me ‘elder brother’ (兄长). He always called me ‘big brother’ (哥哥 gege).”

Now, in context, using 兄长 to address one’s brother in front of an authority figure (like the abbot) is perfectly polite and not suspicious on its own.
However, the fact that Zi Ang himself points it out before Huai Yi even addresses him feels deliberate — a planted moment to make the audience pause. The writers clearly want us to notice this linguistic dissonance, not because it’s a smoking gun, but because it subtly reinforces the air of ambiguity surrounding Huai Yi’s true identity and loyalty.

So, while this alone isn’t hard evidence, it adds texture to his characterization — another thread of doubt in a tapestry of uncertainty.

Exhibit C: A Suspicious Discovery

The abbot reveals that Huai Yi was found thanks to a tip from a servant of the Crown Prince of North Ji — the enemy nation.
When Shu He hears this, he looks visibly unsettled. And rightly so.

Why would a servant of the enemy state recognize an orphaned boy from a massacred Southern Hui family who later became a monk? This connection makes little sense — unless someone wanted Huai Yi to be “found.”

Exhibit D: Motive and Behavior

Huai Yi’s animosity toward Shu He is unmistakable. He throws him to the floor, lies that it was Zi Ang’s order to kill the Southern Hui prisoners — and Shu He never learns the truth.
Why would Huai Yi do this, fully aware that it would only deepen the rift between Zi Ang and Shu He?

His statement, “As long as you are happy, I am willing to do anything” seems like a contradiction. If anyone knows how much Zi Ang desperately wants reconciliation and a real relationship with Shu He, it’s Huai Yi. 

His hatred toward Shu He might stem from jealousy — of Zi Ang’s affection, or of the way Shu He distracts him from his duties. Either way, Huai Yi’s behavior undermines his supposed devotion to his brother.

Exhibit E: Historical Parallels

Duan Huai Yi’s character draws inspiration from Emperor Taizong (Zhao Guangyi), who succeeded the throne after his elder brother Emperor Taizu (Zhao Kuangyin=Duan Zi Ang) died suddenly — without any recorded illness.

This succession was rather unusual in Chinese history; a brother ascending instead of a son was rare. Consequently, rumors of fratricide circulated for centuries. The show’s creative team may be deliberately invoking this ambiguity, weaving the question of Huai Yi’s guilt into historical precedent.

Exhibit F: The Defense

In fairness, Huai Yi did appear genuinely concerned whenever Zi Ang coughed up blood. If he truly was the poisoner, he has an exceptionally good poker face.

He also supported Zi Ang’s rise and rule in many ways, acting as a buffer between him and the court. His execution of prisoners — while brutal — could have been a political move to pacify angry ministers, not an act of betrayal.

As for his cruelty toward Shu He, it may have come from hatred of what Shu He did to his brother — the heartbreak, the rejection, the acceleration of his physical decline.

It’s also possible that Huai Yi sincerely believed the records he cited about the Red Shadow Guards’ “poison,” having been deceived by falsified documents planted by the true conspirators within the court.

Verdict Pending

The evidence against Huai Yi is circumstantial — but compelling.
The inconsistencies around the “poison explanation,” his inconsistent behavior, and the suspicious North Ji connection all cast long shadows.

Whether he was the mastermind, a pawn, or a tragic bystander to palace intrigue remains uncertain.

But one thing is clear: the official story does not add up.
And the timing of Zi Ang’s illness — worsening precisely after his coronation and Shu He’s rejection — feels far too convenient to be coincidence.

The Court Rests.

The jury may now withdraw and deliberate.

Omg, thank you so much!
Not only for reading my ridiculously long post (you honestly made my day — I almost didn’t post it because I thought I was just crazy obsessed and no one would even want to read it 😅), but also for your lovely and insightful reply.

Just yesterday I rewatched the scene where Huai Yi says, “Love gives birth to worry. Love gives birth to fear.”
It hadn’t even occurred to me that this was a Buddhist teaching — but of course, as you pointed out, the amazing screenwriters must have included it for a reason.

Your analysis of episode 11 from Huai Yi’s perspective makes so much sense now. I think I can accept this as one or even the main reason behind his actions: that he wanted to separate Shu He and Zi Ang so his brother would finally give up on him and be "free". (Then again, he should have known Zi Ang would never give up Shu He — the man annexed a kingdom and rebuilt a palace for him!)

So yes, maybe he eventually realized that the rift he created — at the cost of hundreds, maybe thousands of innocent Southern Hui soldiers — only backfired. It caused more pain, and perhaps even hastened Zi Ang’s decline.

To adress the question of Huai Yi's identy:
Yes, Duan Huai Yi was — as far as we know — not adopted, but the true son of the Duans, therefore a South Hui citizen. And while we have this odd dialouge about "elder brother/兄长" and "big brother 哥哥", Huai Yi bears the scars from the snake bite. This would be difficult to find out about and to fake.

So let's assume he is the real Huai Yi. 

We still don't know what happened to him in all those years and if he really was in a Buddhist temple the whole time. Is it possible that he, like Zi Ang, was brought to Ji North too?

In the first episode Consul Wang of the Red Shadow Guard says to Zi Ang "We have news about your brother." It seems like the Red Shadow Guards (or someone high within North Ji's "Intelligence agencies") knew about his whereabouts — hence why a servant of the Crown Prince of North Ji provided the tip to find Huai Yi. 

Someone higher up might have even deliberately withheld this information — and a reuinon with Huai Yi for that matter — to control and exert power over Zi Ang.
After all, North Ji had planned for him to be the next Chief of the Red Shadow Guards, which is an exetremly high-ranking position. A position even potentially dangerous to the throne and therefore only a person completely loyal to North Ji should ever occupy.

It would make sense for them to re-educate Huai Yi, so to speak, into a loyal citizen of North Ji, so that Zi Ang had someone by his side who could guide him...

Zi Ang is of royal blood and therefore all of this is not merely family matters, but deeply political as well.

Am I hearing the grass grow? Am I reading too much into this? I'm not really sure.

What are your views on the mysterious poison Zi Ang suffers from? I'd really like to discuss all of this. 😊

Thank you again, Jury Member Jasprin ‒ your insight will forever be invaluable!

Update - Deliberations by the Jury

 MDL Jury Members have contemplated in regards to Duan Huai Yi in the comment section. Since this discussion will unfortunatley be lost under the new comments in the future, I wanted to provide the link for anyone interested.

 Click the link to read the full conversation  👈😉

Thank you to Jury Members Charbonnel,  MarazulOx, Jasprin  and river11   

the Jury's  deliberations  so far:

Feelings toward Shu He

• C notes Huai Yi never appreciated Shu He’s sacrifices, seeming indifferent or even hostile from the start.
  
  
• M finds it ironic that despite Shu He reuniting the brothers, Huai Yi despised him—possibly out of jealousy or to protect Ji North.
  
  
• J suggests Huai Yi may have had jealous or possessive feelings regarding Zi Ang—possibly even love—leading to tension with Shu He.
  
  
• R believes Huai Yi saw through Shu He’s performance (especially at the festival) and felt he was a threat to Zi Ang—emotionally and politically.

Loyalty and Power

• J and R argue Huai Yi's actions stem not just from cold ambition, but from loyalty to Zi Ang and concern for the North Ji kingdom. He's trying to protect Zi Ang from his own emotional weakness, which could destabilize the kingdom.
  
  
•  R emphasizes the repeated message of the show; to rule, one must be ruthless, and Huai Yi is embodying that philosophy.
  
  
•  J challenges the power-hungry theory, noting that if Huai Yi wanted control, he had multiple chances to eliminate both Zi Ang and Shu He, but didn't.
  
  

Motivations in summary

Twisted loyalty:  Huai Yi's love and loyalty are twisted but genuine, motivating his cruelty. (J & R)

Obssession and jealousy: There is emotional possessiveness toward Zi Ang, possibly romantic or fraternal. (J & M)

Ambition: Huai Yi's ambition to rule (or to maintain order) overrides his morality. (M)

Everyone agrees that Huai Yi is complex and hard to understand. His actions seem driven by a mix of obsessive loyalty towards Zi Ang, jealousy of Zi Ang's and Shu He's relationship and political motivation. Whether his cruel behavior was driven by love, ambition or protection of the kingdom remains open. 

The final verdict is still pending.