Pretty in Pink: a movie about a creative, cynical, working-class girl (Andie, aka Molly Ringwald) who falls for a rich kid (Blane, aka Andrew McCarthy). They're in love. They want to be together and share volumising hair mousse for the rest of their lives.

Sadly, society doesn't understand their love, and Andie spends most of the film being teased and humiliated by Blane's horrible snobby friends. It's emotionally traumatic from start to finish, but at the centre of the film is the most inspiring fashion triumph ever. Let us take you on a journey – a journey from despair to victory, via one very special prom dress.

1. Andie tells Iona that Blane (who, side note, has 'strong lips') has invited her to the prom. Iona tries on her old prom dress and Andie strokes the spotty fabric, murmuring, 'It's a great material...' in a meaningful tone. Andie knows about this kind of thing, clearly.

Emotional state: They're in love, they're going to the prom, there are great dresses in the world: there's so much to be happy about. Giddy optimism.

2. Andie goes dress shopping and encounters an assistant who is so posh and obnoxious that one can only assume she was fired from that Rodeo Drive store in Pretty Woman for being too rude to customers. It turns out that if you want to buy a pink, flouncy, lacy prom dress, it will set you back $650. 

Meanwhile, Blane has suddenly started avoiding Andie's phonecalls.

Emotional state: Why can't she afford a prom dress? Why won't he call her back? What is going on with that shop assistant's giant collar? This is SO UNFAIR, I HATE YOU.

3. Andie's dad comes home with a dress for her. Like the two she's already looked at, it is pink and flouncy. We recall the name of the film.

'Now, I know it's a little busy, but I know you can make something out of it if you need to,' he says. Of course she can. She's the Vivienne Westwood of Illinois.

Emotional state: At least there's a dress. Mild relief. 

4. Blane tells Andie he can't take her to the prom. 'A month ago I asked somebody else and I forgot,' he claims. Oh no he didn't! Andie makes him cry by screaming 'You're a filthy f***ing no-good liar and you didn't have the guts to tell the truth! You're ashamed to be seen with me! Just tell me the truth!' Which is in no way a scary overreaction. 

(James Spader, looking like a 35-year-old bad guy on a yacht, is lurking around the corner wearing a white suit and slip-on shoes and smoking a cigarette, which he stubs out on the floor. Is this the kind of person who frequented high schools in the 1980s?)

Emotional state: Uninvited to prom. Totally failed to play it cool. Utter, utter despair. God he looks fit carrying those books like that.

5. Andie asks Iona if she can borrow her old prom dress. What does she need that for, now that she's got no date? I really hope she's not just going to put it on, sit on the sofa and cry all night while Blane is at the prom and probably dancing with a horsey-looking cheerleader.

Emotional state: Worried.

6. New Order's Thieves Like Us kicks in, signalling that it's time for the montage. Andie holds Iona's dress up against her in the mirror, then turns it upside down (thinking outside the box, see?). 

She's got an idea. She's sketching something. Is it a crown?

The dog looks on quizzically.

She's either making a choker or she's planning to strangle Blane at the prom.

There's lots of cutting and tearing and sewing going on. Presumably she knows what she's doing.

The sketch is really taking shape now. It's definitely not a crown, but it might be a man with no neck hugging a giant tulip.

Emotional state: There've been loads of hints that Andie is a genius fashion designer, so we're expecting something spectacular. Exciting.

7. WOW. That is... not what we were expecting.

But it really does look like the sketch. Hopefully Iona wasn't expecting her prom dress back. Anyway, Andie's not going to sit at home and cry all night. She's going to the prom on her own, because...

Emotional state: BALLSY.

8. When Andie arrives at the prom, every man who glances at her turns into a bewitched fool. Her best friend Duckie is stunned. This is stunned. 

James Spader can't believe his eyes. Sigh, undone tie.  

Blane can't stop looking at that lace detailing.

Emotional state: Smug.

9. Blane immediately and unexpectedly confesses his undying love for Andie: 'You told me you couldn't believe in someone who didn't believe in you. I always believed in you. I just didn't believe in me. I love you.' 

He kisses her on the cheek, murmurs 'Always' and walks away.

Emotional state: What?! He was ignoring her phone calls and uninviting her to the prom last time we saw him! This outcome makes no sense whatsoever.

10. Realising that Blane is a great guy after all, Andie runs after him and they share a passionate kiss in the carpark. The End.

Emotional state: Relieved, if a bit stunned. This entire turnaround can be credited to one magical thing – the dress. Pretty in Pink: an ode to the importance of finding love, transcending social differences, and learning to use a sewing machine.