‘House of the Dragon’ episode 4: Who is the White Worm?

Who was that messenger really working for?
 By 
Sam Haysom
 on 
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A blonde girl and a blonde man in regal dress stand in a garden.
Credit: HBO

So, the latest House of the Dragon episode was a lot.

But now that the dust has settled on all that backstabbing and incest, we need to retrace our steps and work out exactly what was going on.

Who was informing on who? What was the motive? And who is the White Worm, who sent that messenger to Otto Hightower?


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Let's take a look at the evidence.

Who spied on Rhaenyra and Daemon?

A man and a girl in disguise walk through a crowded street at night.
Nothing like a wholesome night out on the town with the family. Credit: HBO

We won't go over all the grisly details from that night, but the sequence of events is still important. It starts when Rhaenyra Targaryen (Emma D’Arcy) goes to her room only to find that her uncle Daemon (Matt Smith) has left her some clothes and a map showing a secret passage leading out of the castle.

She finds him waiting for her and the two leave the Red Keep for a night of exploring the city that ends in a brothel, where things happen. Crucially, though, after Daemon abruptly disappears, we see a young boy watching as Rhaenyra leaves the brothel looking for him.

That same boy is later led through a door in the Red Keep to inform Otto Hightower (Rhys Ifans) of what he's seen.

"Apologies for the late hour, my lord," a soldier says to Hightower. "A messenger brings word from the White Worm."

Who is the White Worm?

A woman in a white dress leans on a bed.
Daemon's former girlfriend has a new job. Credit: HBO

Hold on a minute, White Worm? We haven't heard that name before. So who is it?

When King Viserys (Paddy Considine) angrily demands where Otto heard the rumour about his daughter, the Hand's response is key. "As your Hand I must maintain trusted sources of information," Hightower says, "and this one, as yet, has never led me astray."

Later we get our answer courtesy of a hungover Daemon, who wakes up in a bed belonging to his former girlfriend, Mysaria (Sonoya Mizuno). Only in the three years Daemon has been at war in the Stepstones, it looks like Mysaria has been busy.

"I've left that life behind," she says of her former life working in the brothels of King's Landing. "I learned that the skin trade could only take me so far in this life."

As she's saying this, who should come down the stairs but the same exact messenger who spied on Rhaenyra before informing to Otto. The boy gives Mysaria a handful of money, and just like that we know who our White Worm is.

Mysaria has clearly restyled herself as the leader of a lucrative whisper network, an informer with a web of spies like Lord Varys' little birds in Game of Thrones.

We know how powerful he was, so it'll be interesting to see what the future has in store for the White Worm.

New House of the Dragon episodes are available every Sunday on HBO and HBO Max.

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Sam Haysom

Sam Haysom is the Deputy UK Editor for Mashable. He covers entertainment and online culture, and writes horror fiction in his spare time.

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