Undercover Us Season 1, Episode 4: Episode 4

1

Episode 1

Under tyrant Xie Cizhou’s brutal rule, assassin Si Yao survives a lethal trial to join Wuming Pavilion. A chance encounter with seemingly frivolous prince Xie Ciyuan sparks an alliance neither fully understands.

14 min

2

Episode 2

Assassin bride Si Yao enters a marriage of deception with prince Xie Ciyuan — each plotting against the other, while tyrant Xie Cizhou watches with dangerous amusement.

14 min

3

Episode 3

After a failed assassination, Si Yao and Xie Ciyuan perform a flawless cover-up. When he realizes she can calm the deadly parasite inside him, suspicion turns into something far more personal.

15 min

4

Episode 4

While exposing corruption, Si Yao earns the quiet support of Xie Ciyuan. A hidden message reveals a darker conspiracy and missing women tied to powerful men.

13 min

5

Episode 5

When poison leaves Si Yao near death, Xie Ciyuan drops his mask to save her. A desperate kiss binds their fates — as secrets between them deepen.

15 min

6

Episode 6

As trust falters, Si Yao learns Xie Ciyuan is bound by a parasitic curse planted by his sister, Xie Cizhou — a weapon of control forged in blood.

15 min

7

Episode 7

Compassion turns intimate as Si Yao soothes Xie Ciyuan’s agony. But clues hidden in her blood suggest a past tied to the mysterious Huanhua Valley.

15 min

8

Episode 8

Searching for answers, Xie Ciyuan leads Si Yao toward her buried past but the name “Huanhua Valley” unlocks pain she cannot remember.

14 min

9

Episode 9

Risking everything, Xie Ciyuan sneaks into the lion’s den to see his captive mother — promising freedom as rebellion begins to stir.

14 min

10

Episode 10

A daring prison break exposes a larger conspiracy. Si Yao and Xie Ciyuan uncover ties between the Grand Tutor and the growing wave of disappearances.

14 min

11

Episode 11

Under cover of plague, Si Yao and Xie Ciyuan infiltrate Lu City — where desperate parents reveal the terrifying scale of vanished daughters.

14 min

12

Episode 12

Bloodied but unbroken, Xie Ciyuan closes in on a trafficking ring — as Si Yao uncovers a web linking officials, merchants, and hidden buyers.

14 min

13

Episode 13

A shocking confession reveals Xie Cizhou uses young women’s blood for forbidden alchemy, forcing Si Yao and Xie Ciyuan toward open rebellion.

13 min

14

Episode 14

When Shi An reveals Si Yao is truly Fang Muwan, lost heir of Huanhua Valley, her memory returns — along with the devastating truth that Xie Ciyuan used her heart’s blood.

13 min

15

Episode 15

Heartbroken and betrayed, Fang Muwan walks away. Xie Ciyuan, freed from his curse, realizes the cost of survival may be losing her forever.

15 min

16

Episode 16

Identity unmasked, Xie Ciyuan faces execution, until his mother sacrifices herself, breaking the last chain binding him to fear.

14 min

17

Episode 17

Believed dead, Xie Ciyuan secretly escapes toward Huanhua Valley, while Fang Muwan collapses under the weight of grief and doubt.

13 min

18

Episode 18

On the day Fang Muwan agrees to wed Shi An, a dying Xie Ciyuan crashes the ceremony — begging not for love, but for life.

14 min

19

Episode 19

Forced to witness her marriage, Xie Ciyuan collapses in heartbreak, his damaged body finally surrendering to pain.

14 min

20

Episode 20

Choosing love over duty, Fang Muwan stops her own wedding to save Xie Ciyuan, finally confronting feelings she can no longer deny.

13 min

21

Episode 21

As jealousy simmers, Shi An challenges Xie Ciyuan’s presence. Torn between loyalty and love, Fang Muwan stands at the center of a fragile truce.

13 min

22

Episode 22

Empowered by stolen blood, Xie Cizhou grows stronger, while Fang Muwan and Xie Ciyuan prepare for a final reckoning.

14 min

23

Episode 23

War reaches Huanhua Valley. Amid betrayal and sacrifice, Fang Muwan falls into Xie Cizhou’s hands as allies perish.

14 min

24

Episode 24

In a brutal final clash, Shi An sacrifices himself, Xie Cizhou falls, and love proves irreversible. Years later, Fang Muwan and Xie Ciyuan rule apart — bound by memory, not destiny.

13 min