The Crystal Cuckoo – Series Review | Netflix

THE CRYSTAL CUCKOO on Netflix is a new crime thriller series from Spain (org. title: El cuco de cristal). It features a serial killer story spanning many decades in just six strong episodes. Read our full review of The Crystal Cuckoo series here!

THE CRYSTAL CUCKOO is a new Netflix series with a crime thriller plot. It’s a serial killer mystery where you will get all the answers before the end of episode six. In fact, episode 5 is quite a game-changer as it goes back and shows us what has happened.

With a total of six episodes, this Spanish series (org. title: El cuco de cristal) packs quite the punch. It comes from the same author as The Snow Girl, which has two seasons out on Netflix. All six episodes were watched for this review – because it’s a great show!

Continue reading our review of The Crystal Cuckoo series below. Find it on Netflix from November 14, 2025.

From heart attack to murder mystery

The Crystal Cuckoo begins with Clara Merlo (Catalina Sopelana) suffering a massive heart attack. Fortunately, she’s at work as a first-year medical resident, so she couldn’t have a heart attack in a better place.

Once she wakes up, a month has passed, and she now has a new heart. Having been kept alive by machines, she was fortunate enough to get a second chance. As Clara is finding her way back to life, she can’t help but wonder about the donor.

No, not because she’s getting strange visions or has foreign memories suddenly. Those plot elements have been used for several horror movies. Even very efficiently. However, this is not a horror story; it’s a crime thriller mystery, which indirectly involves her donor.

No, that’s not a spoiler, but simply to say that many strange disappearances have happened in the small town, where Clara’s heart donor, Carlos, lived.

Anyway, Clara decides to visit his family.

A picturesque town with secrets

Sometimes, a crime thriller mystery like The Crystal Cuckoo will play out in a town that suddenly feels like something out of The Hills Have Eyes. This is not that kind of small town. Instead, it’s a picturesque and enigmatic small town full of kind people.

And yet, the town also seems to have had more disappearances than could be expected. Sure, some people up and leave their families, and others run away as teenagers, but this goes beyond that.

For Carlos, the man who previously had Clara’s new heart, it was his father who disappeared. Now, Clara is staying in the family’s house, where the mother is still grieving her son’s death (and dealing with her husband’s disappearance decades earlier).

One family tragedy after another

Carlos’s own dad, Miguel Ferrer, was a police officer and an overall good guy, who also had experienced loss; His own sister disappeared years earlier. In fact, Miguel was still searching for answers when he disappeared. Could it all be connected?

Well, yes, and in ways that are even more sinister than you’ll likely imagine after the first few episodes of The Crystal Cuckoo.

There are many time jumps in this Netflix series as we follow the present (or near present) and then go back 20 years. It’s all made very obvious by telling us what year we’re in. Also, you can tell by the aging of the characters.

Watch The Crystal Cuckoo series on Netflix

The new Netflix miniseries The Crystal Cuckoo (org. title: El cuco de cristal) is a new adaptation of a Javier Castillo novel. He also wrote the novel that was made into the Netflix series The Snow Girl, and now another one of his best-selling novels is being adapted.

This Netflix adaptation comes from Jesús Mesas and Javier Andrés Roig (The Snow Girl), and the episodes are directed by Laura Alvea (Animas) and Juan Miguel del Castillo (The Gypsy Bride).

The cast of The Crystal Cuckoo also features several familiar faces for fans of Spanish production. These include star Catalina Sopelana (The Gardener), Alex García (Unknown Origins), Itziar Ituño (Money Heist), Alfons Nieto (Burning Body, Elite), Tomás del Estal (Gangs of Galicia), and Iván Massagué (The Platform).

If you’re in the mood for a strong crime thriller mystery, then you do not want to miss out on The Crystal Cuckoo. It features an insanely sinister and eerily realistic serial killer story that feels like something you could just as easily have come across on the evening news.

All 6 episodes of The Crystal Cuckoo will premiere on November 14, 2025.

Details

Directors: Laura Alvea, Miguel del Castillo
Script: Jesús Mesas, Javier Andrés Roig
Stars: Catalina Sopelana, Alex García, Itziar Ituño, Iván Massagué, Alfons Nieto, Tomás del Estal