How many heel turns can you list that have properly haunted you? Whose sense of injustice you couldn’t shake days or weeks later, even when you know it’s probably a smart booking decision? I have vivid memories of shedding tears over Steve Austin’s betrayal of the WWF during the 2001 invasion angle (I know you’re not supposed to like that angle, but it falls right into the middle of my childhood nostalgia window). Kevin Owens’ brutal crashing of Sami Zayn’s coronation party hit like a ton of bricks, as, in its own ludicrous way, did Famous B’s attack on Mascarita Sagrada at the back end of Lucha Underground’s second season. Now I have another turn to add to the list. As of last month Io Shirai has gone rogue, and it has dramatically shifted the landscape of World Wonder Ring Stardom.

For those who don’t know, Io, last seen flying off the roof of Dario Cueto’s office, is the ace of Stardom. She holds the company’s main belt and is the best wrestler in the world. At the top of the company’s pecking order, she is joined by the two competitors that followed her to Lucha Underground: Kairi Hojo, who claims to be a real pirate and is unanimously viewed as having the best elbow drop in wrestling, and Mayu Iwatani, the youngest of the three, whose entrance gear aesthetic was once described by a friend as “Admiral Space Eagle”. Io, Kairi and Mayu recently held the company’s trios titles under the team name Threedom, but lost them to the villainous stable Oedo Tai in October. Io and Mayu also have extensive experience tagging together as Thunder Rock. They lost their belts to Oedo Tai in June. They also had MOTY contender for the top title in May, which may be relevant later on.

Of these three so-called “daughters of Stardom”, Mayu is maybe the least talked about, and definitely the least demonstrative. Her individual promos are shy: in the clip that precedes her match against Saori Anou at Stardom’s most recent Korakuen Hall show, Mayu’s lines are short and softly spoken; her gaze wanders down to her feet or to the side of the frame, avoiding eye contact. Throughout this match, Mayu carries herself with a compelling kind of quiet, dialled-in callousness. She doesn’t play to the crowd a whole lot or do too much emoting, but what little there is communicates in no uncertain terms that Anou, a relative newcomer to joshi, is in over her head and is about to be taken to school.

It’s different when she’s with Io. Mayu seems more animated in the presence of her partner. A little way into a tag team tournament match against the Oedo Tai pairing of Kris Wolf and Kagetsu, Mayu reclines on the ring apron in an homage to Tetsuya Naito while Io flies through the ropes and into their opponents. Later, Mayu does a kind of Damien Mizdow thing from the ring ramp, imitating Io’s gestures while she chops the heck out of Kagetsu. They work together and they win, despite some extremely blatant foul play from Oedo Tai. Mayu can win matches with or without Io, but it’s a different version of Mayu we see in each case. Io helps Mayu to have fun out there. She can come out of her shell and put on more of a show. She’s a more rounded performer with Io by her side. Their friendship is extremely precious.

Thunder Rock’s penultimate and final matches took place on the same night, 11 November, in Shinjuku. In a promo before the semi-final of the aforementioned tag team tournament, Mayu is in ebullient mode, stealing Kaori Yoneyama’s catchphrase (“we are READY!”) and then jokily squaring up to the camera like “what are you gonna do about it”. Both Io and Mayu agree that their bond is stronger than that of their opponents, the rookie pairing of Momo Watanabe and Jungle Kyona. But there’s trouble ahead. Late on in the match both teammates are in position for Mayu to make a hot tag but she chooses to stay and fight and receives a hard kick from Momo for her troubles, leading to a near fall for the rookies. After a bit of jostling on the apron with Kyona, Io barges into the ring to fend off Momo with a flurry of vicious strikes, before handing her victim over to Mayu for a match-ending Dragon Suplex. When Mayu can’t get Momo up, Io climbs to the top rope and summons Mayu, who still has Momo in a full nelson hold. You can guess what happens next. Io launches herself into a dropkick but Momo escapes; Io nails Mayu and after struggling to regroup the two are then sent to the mat again by a big double lariat from Kyona. The rookies all but have it won from here, but Mayu is able to dodge a knee strike from Momo and roll her up for the three count.

So Mayu gets the win for her team, but not without some friction. Mayu’s decision making and inability to capitalise on Io’s interference nearly cost her team. In a short promo before the tournament final against Kairi Hojo and Yoko Bito, Io apologises to her pal for being too “aggressive” and catching her in the crossfire. Two minutes into the match and she’s at it again, refusing to give Bito a clean rope break, nailing her with repeated blows to the chest. Bito recently challenged Io for the belt after winning Stardom’s version of the G1 Climax, and it brought out a side of the champion that a WWE commentator would likely describe as a “mean streak”. Still, Thunder Rock seem cohesive, with the two hitting stereo diving crossbodies from the top turnbuckle to the floor and then posing together on the apron. At one point Mayu calmly drags a supine Kairi over to her team’s corner, holding her in place by standing on her injured leg and making contemptuous “surfing” motions with her arms. Io then lays out the limb and drops both of her knees onto it from a great height, before ambling across the ring and just slapping Bito in the face for no reason. Mayu’s brutality is sillier than Io’s, but they’re on the same page.

That earlier tension hasn’t gone away, however. A little while later, Mayu hits Io with a superkick that was intended for Kairi. The momentum shifts as Bito enters the fray and starts serving Io some receipts. With the two fighting for control of a vertical suplex, Mayu comes in to add reinforcement but Bito manages to get them both up and over. Io is not about getting outwrestled by Bito, and clearly lays the blame for this on Mayu. About ten minutes of ridiculous back-and-forth wrestling with Kairi and Bito just about maintaining the upper hand later (seriously, seek out this match) we get to the moment of no return. The way it’s pulled off is ingenious. Io and Mayu are setting Kairi up for another double team spot where one of you holds the opponent in place and the other lays them out with a strike. The spot that can only ever go wrong. Kairi wriggles out of Mayu’s clutches and Io pulls her punch just in time. But then Io takes a beat, and punches Mayu anyway. Mayu collapses to her knees, both out of shock and because she’s just been punched really hard. Io retreats to the apron while Mayu gets worked over by Kairi, and initially displays some concern, but when Mayu escapes and tries to make the tag, Io bails. Mayu is abandoned and visibly dejected, but when Kairi and Bito hit her with a tandem finisher, Mayu kicks out. She is so brave. The match is finished for real a minute later, but only after Mayu eats two more back-to-back finishers, including a signature Hojo elbow drop.

There are twenty minutes of fallout included in the version of the match uploaded to Stardom’s video-on-demand service, each one more heartbreaking than the last. Kairi and Bito try to celebrate their tournament victory but everyone’s clearly more concerned with what just happened between their opponents (Io will later destroy their trophy as well). Mayu is on her knees in the ring this whole time. While the victorious team deliver the mandatory promo, Mayu crawls over to the ropes and just sits there, dumfounded. Io comes back and proceeds, in the coldest tones imaginable, to admonish her former partner for looking so miserable. Then she brings out her new partner, who is hooded and supposedly anonymous at this point but who everyone appears to have already identified (Kairi makes a couple of jokes about this and they provide some brief comic relief in this sea of woe). Io announces that Thunder Rock were supposed to win the tag league and then join up with this mystery partner to take back the trios belts. But she’s changed her mind. Mayu is lying in the corner listening to her best friend trying to justify betraying her, and Io boots her in the face. Fuck. Now the kicker: Io had seen a fire in Mayu’s eyes around the time of their title match in May, but Mayu hasn’t worked hard enough at improving her game since, so Thunder Rock is through. Oh, and Threedom is through too, which evidently has everything to do with Io’s disapproval of Kairi having teamed with Bito in this tournament. Bito really gets Io’s dander up for some reason.

Io and her mystery partner (who is definitely not a returning HZK, no sir) leave the ring and it’s left to Kairi and Bito to pick up the pieces. Mayu’s face here is a picture of heartache. She’s so reduced, just glazed and quietly crying while her two co-workers try to offer her all the support they can muster. This isn’t just rejection by a friend, this is expulsion from the unit that helped Mayu be happy as a performer, and she’s being expelled precisely because of that happiness. Io only wants to work with the quiet, callous Mayu that pushed her to the limit in their title match, not goofy Thunder Rock Mayu with her crowd pandering and fangirl impressions. But that’s who Mayu is when she’s teaming with Io, because win or lose, she just loves doing flippy shit by Io’s side. Now it turns out that that love is not reciprocal, that Io can do without it. She’s the ace, nobody can touch her, and she’s going to look out for number one. Kairi and Bito tell Mayu they’re right there with her, but it’s not the same, is it. With Kairi’s help (we all need a friend like Kairi here), Mayu manages to hold back the tears long enough to sputter out a few words about how she’s a winner, and how she’ll beat Io the next time they meet. She doesn’t look like she quite believes it herself yet, but it’s what she needs to work on believing. She needs to prove to Io that their friendship hasn’t held back her development as a wrestler, so that Io can respect her and they can be friends again, and she’s going to prove it and make everything better by beating Io’s ass and taking her damn title.

A couple of weeks later, in Shinkiba, Io’s mystery partner was revealed as the returning star everyone thought it was, and Io (with new “Io Dark” gear) gave a silent and moody promo before the match, because she’s evil now, but maybe also a tiny bit ashamed of herself. And Mayu got betrayed again, this time by Momo Watanabe, who seems like the last person you’d turn heel. But there wasn’t quite the same level of pathos this time round: Mayu’s already dialled in and focused on settling this score. Those moments when Io and Mayu were in the ring together had an intensity, both emotionally and physically, that surpassed even their title match in May. And based on what happened that night in Shinjuku, I haven’t been this emotionally invested in the outcome of a match since Sasha Banks v Bayley in Brooklyn. We’re only just into the 2017 Stompies calendar, but this could be the feud of the year.