Rachel Flax is glamorous, and a whole lotta trouble. But it’s her hair that says it all – the arc of Mermaids follows the rise and almost-fall of a vast bouffant filled with illicit sex and Scotch, sliced by a fringe as sharp as her tongue. Rachel’s daughter, Charlotte, is the antithesis of her wild mother, but her hair also tells a tale. A neat little bob, pulled back from her face with an Alice band, it’s less than half the height of her mother’s impressive bouffant, but hides double the secrets.

In fact, you can trace all the winding traversions of the plot right down to the hair that stars in it….

1. As Mermaids begins, Rachel Flax is having an affair with her boss, her hair is riding high on her head. It’s as black as a raven, but before it verges on severe, she kinks the ends with a bunch of rollers for a playful hint at the feminine wiles lying beneath the aggressive sexuality. Then she gets dumped, immediately washes the adulterer right out of that barnet, and as she’s done 17 times before, decides it’s time to move herself and her two daughers, Kate and Charlotte, to another state.

2. A wannabe nun and long-suffering daughter of a veritable she-devil, Charlotte’s hair is as prim and proper as her little Christian figurines and religious reading material. Still, it’s shiny and youthful where Rachel’s occasionally verges on the absurd. That must drive Rachel CRAZY.

3. In the aftermath of the mother’s failed love connection, Charlotte and Kate find themselves in Boston. While Rachel is ready to raise new hell – hair loftier than ever – Charlotte is not sharing her excitement for a new adventure. So of course her hair is flat as a pancake, that twee Alice band holding it rigidly in place until a habit can cover it once and for all.

4. The family’s debut in town starts at the shoe shop, where Rachel is busy hooking a live one – shop owner, Lou – with her whopping great big bonce. Charlotte – as fastidious as ever – meets her own dream playmates: a couple of nuns. She really is the sweetest little Catholic-Jewess there ever was. 

5. Rachel’s beehive has won out – Lou tells Rachel to meet him at the town high school parent’s evening and so for the first time in Charlotte’s academic career, Rachel is off to meet her teachers, back comb burrowing away throughout a great 1960s wave of wonder. Lou is understandably hooked.

6. Rachel invites Lou for breakfast. Not for tea and toast, but for a big old slice of Flax with a beer chaser. The beehive is softened with extra curls and texture through it as Rachel plays out her notably brief seduction routine. It probably took longer to sculpt her hair than it did to get Lou racing upstairs to her boudoir. 

7. The cigarette is lit, the sheets are mussed, but that hair is still intact. It’s rounder maybe, more voluptuous perhaps, but even Lou’s best moves can’t shake out Rachel’s teasing. Or, as it turns out, her resolve to stay single. It’s her sartorial armour. And interestingly, the heart-on-sleeve Lou has very little hair himself…

8. Charlotte has kissed the local heartthrob, caretaker Joe. She thinks she might be pregnant, the as yet undefiled mother of the next Italian-Jewish messiah. She goes to seek advice from mommy dearest who is reading Peyton Place in the tub. Charlotte’s hair is growing out and looks a little tiny bit…looser. Uh oh, there’s surely a storm brewing. Rachel on the other hand is all tendrils and a decidedly softer crown. Even the fringe has silky breaks in it. Lou is making headway, clearly, at breaking down Rachel’s defences.

9. When Charlotte can’t bring herself to ask Rachel for advice, she goes straight to a gynaecologist to check out that holy vessel of hers. He confirms she is intact and without child and she’s allowed to go on with her Alice-band-wearing business, with just a little hint of a kink through the ends of her little bob. As she realises there ISN’T always a burnt-at-the-stake consequence for wanton lust, it the beginning of the end of her frigidity?

10. Meanwhile, Lou has his feet firmly under the table, and the walking beehive is starting to feel characteristically claustrophobic. When New Year’s Eve comes round and Rachel has to pick a costume for the party, she plumps for slutty mermaid. The vast blonde curls send a clear signal: she’s out to wreak havoc. She is set to self-destruct, first to sabotage her too-good-to-be-true relationship with Lou and then to enrage Charlotte by kissing her crush, Joe. Blonde curls always spell trouble.

11. Two can play at that game! Charlotte dons her mother’s most whorish dress, sexy little kitten heels and most importantly, works up an ebony puff of frothy hair on her head. She teases until she’s ready to slut it up.

12, It’s all gone wrong, as it so often does in movie-land when a teenager gives in to her base desires. While Charlotte was busy humping Joe and his leather bomber jacket, little Kate fell into a river and nearly died. While she’s in hospital, Rachel and Charlotte swap a few home truths and their hairdos start to even out. Rachel’s hair drops a few centimetres with all the stress of her daughter’s coma, while Charlotte’s bob has been shagged into disarray. See, stress is a real leveller when it comes to hair. Either that, or Charlotte’s sexuality has awakened her mother’s genes within her rapidly swelling follicles, while Rachel’s relative lack of a sexlife since she gave Lou the heave-ho has left her feeling a bit flat. Regardless, they’re both in need of a blowdry, stat.

13. Kate recovers, Joe leaves to start afresh somewhere new, and a novel sense of calm descends on the house of Flax as Charlotte and Rachel settle on a more honest relationship. Charlotte is no longer a devout Christian, so her hair is looser, freer and way sexier. The Alice band has gone, along with her virginity. Rachel is giving a committed relationship with Lou a go, leaving her hair looking softer, glossier and less helmuty. 

14. We leave the Flax women dancing in the kitchen. Both Charlotte and Rachel wear their hair half-up-half-down – so both have reached an equilibrium of part-slutty, part-sensible. Happy days.