House of the Dragon viewers not happy about upcoming casting change

House of the Dragon is set for a major casting change and the news hasn't gone down too well with some fans.

We're three episodes into the Game of Thrones prequel and already, the HBO show has proven to be a hit with audiences.

It's also give viewers enough time to grow accustomed to certain characters, including Milly Alcock as Princess Rhaenyra Targaryen.

But when the timeline jumps forward midway through the season, the 22-year-old actress is set to be replaced to reflect the time change.

After five episodes with Alcock as the fiery princess, she'll be replaced by 30-year-old star Emma D’Arcy.

The same goes for Alicent Hightower, played by Emily Carey, with Olivia Cooke taking over in later episodes.

Leana (Nova Foueillis-Mosé) and Laenor (Theo Tate) Velaryon will also be replaced, with actors Nanna Blondell and John MacMillan taking on the roles respectively.

That's quite the reshuffle, but unfortunately there's no avoiding it as the show has to span such a wide time frame, and HBO certainly made the fact known in its promo materials.

While we have no doubt the new actors will shine in their portrayals of the characters, some viewers have taken to Twitter to share their upset, most notably in relation to Alcock who has become a fan favourite as Princess Rhaenyra.

In response to a post about the cast change, one person wrote: "I like Rhaenyra's current actress so much though," alongside a sad emoji.

Another said: "Thats what I was thinking, I haven’t seen the replacements performance but they don't seem alike to me."

Elsewhere, one Twitter user wrote: "Actual nightmare that Milly Alcock is leaving the show," while another commented: "They’re changing rhaenyra's actor midseason?? NOOOO she's the best part."

A third added: "Milly Alcock as young Rhaenyra Targaryen is one of the most perfect castings ever, i’ll never get over it #HouseOfTheDragon."

According to those responsible for the show, the decision to replace the characters was made ‘early on’.

Co-creator Ryan Condal said: "It's a conceit but I think it does work, having watched it a bunch of times.

"The people that are truly children in this are the ones that get recast. And the people that are already adults when we meet them, we age them up through hair and makeup and sometimes the actors change their voice."

House of the Dragon continues on Sky Atlantic tonight, 5 September, at 9.00pm and On Demand from 2.00am on Sundays.