Gwyn and Catrin: The evil twin theory.
What if the evil 'lightsinger' hinted at in ACOSF isn't Gwyn, but is instead her twin sister, Catrin...?
(Note: I have no stake in the elriel vs gwynriel debate, and this theory isn't in favour, or against, either of these ships. If anything, I think this theory offers a compelling storyline for Gwyn's character to explore; one that doesn't entirely revolve around men and love triangles).
In ACOSF, we are introduced to the concept of "lightsingers." These are beings who "lure" their prey by appearing as "friendly faces."
"There are lightsingers: lovely, ethereal beings who will lure you, appearing as friendly faces when you are lost. Only when you're in their arms will you see their true faces, and they aren't fair at all."
Given that they reside in rivers (or other bodies of water), they can be linked to the various mythologies that describe the 'evil mermaid.'
This connection isn't far-fetched, considering that it was near confirmed by SJM herself in a 2015 interview (when asked about the use of mythology and folklore in her books):
Here is a transcript of what SJM says:
Interestingly, the rusalka are near identical to how the lightsingers are described:
You are drawn to them/they lure you
When you get close to them, they drown you.
Most of all, the rusalka (similar to the sirens) lure their prey by using their enchanting voice.
And, for even further confirmation, SJM's (now deleted) Pinterest board featured many images of the rusalka. For example:
Given that Gwyn also has an alluring voice - one that seemingly enchants both Nesta and Azriel in ACOSF - one of the more popular theories within the fandom is that Gwyn is a lightsinger. However, given the fact that lightsingers are evil beings, this calls into question whether Gwyn too, is villainous.
There are canon hints in the text to support such an idea; for example, in ACOMAF, Rhys mentions that some priestesses are not to be trusted (and insinuates that they have a hidden agenda).
Similarly, Elain's gift to Azriel - earplugs - is rather curious, as some strains of folklore/history state that earplugs were first invented for sailors as 'hearing protection' from the sirens (as it was thought that the earplugs would stop the effect of their enchanting voices). Evidently, Elain is also a seer; did she see something in the future, and know that Azriel would need such protection...?
However, although Gwyn likely has lightsinger powers, I don't believe that she is the 'evil' lightsinger that the text is hinting to.
Instead, I believe the 'evil' lightsinger is Catrin, Gwyn's twin sister.
As my first piece of evidence (and knowing that SJM isn't one for mere coincidences), recall the song that the Weaver sang in ACOMAF; the song about two sisters, with one sister murdering the other.
"There were two sisters, they went playing,
To see their father's ship come sailing...
And when they came unto the sea-brim,
The elder did push the younger in."
A key detail about the Weaver's song is that one sister kills the other by drowning her. Lightsingers also kill their victims via drowning:
"The horror of it is the last thing you see before they drown you in the bog. But they kill for sport, not food."
However, the Weaver's song isn't just a song that SJM made up. Instead, it is based on the ballad of the "Twa Sisters" (or, otherwise known as "The Cruel Sister"), which recounts the same tale of two sisters (often twins!), where one murders the other.
Most notably, in many variations of this ballad, it is stated that one sister - the victim - is fair and light-haired, and often associated with the light. She is seen as kind and loving. Just like Gwyn.
[Art by isis_villalobos_art]
In comparison, the evil sister, who is often described as "dark haired," is seen as a personification of the darkness. She is often described as temperamental and jealous. Perhaps this is similar to Catrin, who SJM made sure to describe as being as "moody as the sea"...
[Art by isis_villalobos_art]
Although I don't believe that Catrin will murder Gwyn (or at least, I hope not!), I do believe that the Weaver's song is symbolic of Gwyn and Catrin's relationship, and foreshadows Catrin's role as the evil twin sister.
As further evidence of this, there was a particular piece of artwork that SJM saved to her 'Story Kernels' Pinterest board. When I reverse-image searched this art piece, it was titled "Good vs Evil." And, as you can see, it depicts one sister drowning the other...
However, you're most likely thinking: "but Catrin is dead!" Well actually... I don't think she is.
To explain how this would be possible, we first need to explore Gwyn and Catrin's mysterious lineage.
Gwyn and Catrin's family tree.
SJM provides an unusual amount of information regarding Gwyn and Catrin's lineage, which has led many to believe that it will be of great importance. For starters, Gwyn states that her grandmother "seduced" a High Fae male from the Autumn Court.
"My grandmother was a river-nymph who seduced a High Fae male from the Autumn Court."
I believe that male is Lucien.
Gwyn then goes on to explain that her mother fell pregnant during Calanmai, where she partook in the Great Rite with a "male stranger."
"She partook in the Great Rite when she was of age, and I, we - my sister and I, I mean - were the result of that sacred union with a male stranger."
Again, this is an unusual amount of information about a side character's conception. Evidently, this particular passage causes readers to think of Tamlin - and, that's exactly who I think Gwyn and Catrin's father is.
Understandably, you're probably thinking that Lucien and Tamlin fathering the same line of women is super messed up. And I agree - but, I think that's the point. I believe that it was done on purpose, and orchestrated by none other, than Ianthe.
In fact, I believe that Ianthe is Gwyn and Catrin's grandmother.
As evidence of this, Ianthe is the only other character with "teal" eyes. Ianthe was also described as having a "supple" body, which is another word for "pliant" (the same word used to describe Gwyn's bones).
And, knowing that lightsingers appear as a "friendly face" when you are "lost," it is rather interesting that Ianthe showed up (again) when Tamlin and Feyre were suffering after UTM, using the opportunity to manipulate those around her. Coupled with this quote about her:
"A mask over a face of decay"
I get the feeling that Ianthe was the original lightsinger.
By extension, this also suggests that Ianthe must have been a water/river nymph (given Gwyn and Catrin's own lineage). Although Ianthe doesn't possess the telltale webbed fingers, it is implied that lightsingers can shape-shift, or perhaps glamour their true appearance. Because, it's surely no coincidence that Ianthe, in Greek mythology, was a famed water nymph.
Further, although Ianthe's true motives were rather vague and hidden, it was clear that her goals were centred around creating powerful heirs with High Lords. She once propositioned Rhys with this exact intention, stating their offspring could "rule Prythian."
"Do you know what a union between us could do for Prythian, for the world?" she said, eyes devouring him still.
"You mean yourself."
"Our offspring could rule Prythian."
Cruel amusement danced through him. "So you want my crown - and for me to play stud?"
Then, following this exact scene, in that same chapter, Feyre suggests that Ianthe approached Lucien in a similar manner. However, unlike Rhys, Lucien wasn't in a position to say no.
I believe this is how Gwyn and Catrin's mother was born.
"I swallowed hard, my heart thundering. "She - she didn't act that way at..."
Lucien.
Lucien had hated her. Had made vague, vicious allusions to not liking her, to being approached by her -
I was going to throw up. Had she... had she pursued him like that? Had he... had he been forced to say yes because of her position?"
However, I believe that Ianthe kept the pregnancy a secret. Then, when she left for Vallahan (around 50 years ago), she left her child behind. This perfectly explains why Gwyn describes her mother as being displaced among both the Spring and Autumn Courts, but then eventually seeking refuge at the temple of Sangravah.
Then, when she was older, Gwyn and Catrin's mother participated in the Great Rite with Tamlin. She falls pregnant - something that Gwyn suggests that the father (Tamlin) was never informed about.
Perhaps Ianthe had made contact with her daughter and coaxed her into this, or perhaps it was a mere coincidence. However, it likely explains the Welsh origins of Gwyn and Catrin's names, given that the Spring Court is geographically aligned with Wales (as Prythian is a map of the UK).
It also aligns with Tamlin's character being inspired by the Ballad of Tam Lin - which is all about Tam Lin fathering an unexpected child.
Most importantly, this theory suggests that Gwyn and Catrin are directly descended from three High Lords (or heirs to); Helion, Lucien, and Tamlin.
Just as Ianthe always wanted.
Not only does this make Gwyn and Catrin immensely powerful, but it also explains their physical characteristics:
Gwyn with her Autumn Court hair, and Ianthe's teal eyes.
Catrin with Helion's "onyx" hair (and although we don't yet know Catrin's eye colour, I am willing to bet they are green - the same as Tamlin's).
It also explains their magical abilities. Many have already theorised that Gwyn possesses Helion and Lucien's Day Court abilities (given that she 'glows').
In contrast, (and in a similar vein to [CC Spoilers] Lidia and Hypaxia inheriting different powers despite having the same mother), I believe that Catrin inherited Tamlin's abilities - to shape-shift herself, but also other people.
It's because of Tamlin's power that I believe Catrin is still alive. When Hybern's soldiers attacked the temple, I theorise that Catrin shape-shifted the appearance of someone else to look identical to her, and they were then killed in her place. That way, Catrin had the means to escape without anyone else knowing.
Alternatively, if you believe this to be a far-fetched idea, or you perhaps have a different theory about Gwyn and Catrin's lineage, then we can instead refer back to the rusalka mythology. Notably, the rusalka were said to be the spirits of deceased women:
The rusalka were also said to have shapeshifting abilities.
Thus, whether Catrin is still alive due to inheriting Tamlin's own shapeshifting abilities, or whether SJM is instead keeping true to the rusalka myth, and Catrin is a deceased, haunted spirit capable of shapeshifting on her own... both can work here.
Some may then question Catrin's motive in all of this - and to that, I point to Koschei. Interestingly, both Koschei and the rusalka are key figures in Russian mythology (and often intersect in various Russian tales and folklore).
It's also curious that Koschei has been "preparing" for Azriel (and/or his friends) for "months" now. I can't help but wonder if such plans involve Catrin. Koschei can't leave his lake, but Catrin can in his stead...
Ultimately, I believe that Catrin is once again using her shapeshifting abilities. But this time, it's to appear as Gwyn.
SJM even went out of her way to explicitly tell the reader that Gwyn and Catrin's scents are "nearly identical," so such a rouse would work...
"He didn't believe me. So he grabbed Catrin, because our scents were nearly identical, you see..."
As such, and as controversial as this may be, I think that the one time we have seen Catrin disguised as Gwyn, was in the Azriel bonus chapter.
Recall that this chapter detailed the events of the Winter Solstice, meaning that it occurred about 3/4 of the way during the events of ACOSF. Days after the Solstice, Gwyn was invited to Nesta's house. However, as described in the text, it wasn't easy for Gwyn to leave the safety of the library to attend the sleepover:
"Gwyn's head popped in, and she scanned the room before entering"
"Gwyn's smiled, though her pulse pounded wildly against the column of her throat"
"[Gwyn] said in a hushed voice, "I sometimes wonder if I shall ever have the courage to go out there again. I fear every day that I won't"
Yet, supposedly before this sleepover, as detailed in Azriel's bonus chapter - Gwyn was completely alone, in the middle of the night, practicing in the training pit?
But, who else has a knack for training? Catrin. As stated by Gwyn herself:
"I knew Catrin would have been the first to sign up for training"
Thus, I believe that the person Azriel saw at 2 am in that bonus chapter, was Catrin - disguised as Gwyn.
Who has been watching him - watching all of them - for some time. Perhaps this is why Azriel's shadows weren't alerted to her presence, or why Azriel heard that "faint singing," akin to that of a lightsinger.
(As a side note: some may argue that during the sleepover scene, Gwyn outright mentions that she had left the library to "hack at the ribbon" in the training pit, and thus, it's perfectly plausible that it was Gwyn training in Azriel's bonus chapter - and not Catrin. However, Gwyn wasn't very specific when stating this, and at this point, there had been plenty of other instances of Gwyn attending that same training pit - instances that occurred in the safety of broad daylight, and surrounded by other people. Two very different scenarios...).
It is interesting to note that in Celtic mythology (which seemingly inspires a large chunk of SJM's work), there is a famous horror story featuring the character "Lady Gwyn." The mythology around Lady Gwyn describes her as a woman "pretending to be a lovely, beautiful soul" who would then "lure and kill any lost journeymen caught wondering through the night." This sounds just like a lightsinger.
Lady Gwyn is also depicted as a woman who has been decapitated - she is headless. This is exactly how Catrin was said to have been killed. Is this a (very morbid) clue...?
But, it gets even crazier (and shoutout to Sam for informing me of this connection!)
In the tales of King Arthur (and evidently, Arthurian legend has also greatly inspired SJM's work), there is a well-known love triangle between Guinevere, and a certain Lady Elaine...
But here's the kicker: Guinevere had an evil twin sister. She was known as the "False Guinevere," as she looked identical to the real Guinevere. She then used this to bewitch Arthur (her husband), turning him against the real Guinevere.
Is that not... exactly what this theory is suggesting...?
It all comes back full circle.
Recall that at the end of the Weaver's song, it is suggested that the evil sister doesn't get away with her crimes. Instead, someone playing a viol (or a fiddle), reveals the evil sister's secrets, and saves the day.
What character do we associate with the viol or fiddle? Tamlin.
Who, as per this theory, is said to be Gwyn and Catrin's father. It all aligns.
