It always surprises me when I check the IMDb credits for a film and spot that a title is the director’s feature-length debut, especially when said debut is as charming as Sweetheart is. Marley Morrison has excelled in this instance.

Nell Barlow is AJ – or April to almost everyone else – your typical slouchy, grumpy 17 year-old girl, uninterested in everything, especially her little sister Dayna (Tabitha Byron). When mum Tina (Jo Hartley) arranges for the family to stay at a holiday park for a week, AJ can’t think of anything worse, especially when she discovers they’ll be accompanied by her heavily pregnant older sister, Lucy (Sophia Di Martino).

On arrival, AJ scopes out the site, refuses to go swimming, sulks on a sun lounger, and generally has a slouchy, grumpy time. But when lifeguard Isla (Ella-Rae Smith) catches her eye, things seem to be looking up. Welcomed into the staff side of the camp by Isla, the pair bond over an awkward evening of drinking and drugs, neither of which AJ is accustomed to. After taking herself outside for a moment to calm down, she spots Isla hanging out with one of the lads, breaking AJ’s tiny teenage heart.

This making her perpetual bad mood even worse, AJ stomps around the family’s cabin, badgered by Tina as to why she’s so upset. As tensions and voices rise, AJ’s only source of solace is Lucy’s partner Steve (Samuel Anderson), who sees through her frowning to know that something else is going on.

Taking cues from the likes of popular British comedy The End of the F***ing World, from the start we hear every comment crossing through AJ’s mind, giving us a passenger seat into every minute she spends moping around the holiday park. When she first meets Isla, we hear how AJ wonders how she smells – ‘I bet she smells nice’. We hear every self-conscious, overthinking thought, as AJ tries to tackle her shyness…and sexuality. Confused as to who she is versus who she thinks her mum wants her to be, AJ’s week is full of ups and downs as she wrestles with messy teenage hormones, parental expectations…and sitting through painful evening entertainment.

Barlow (Behind Her Eyes, Doctor Thorne) as AJ is brilliant casting, perfectly encapsulating the snarky, sarcastic wit of many teenagers. Facing off against Hartley’s (This Is England, After Life) Tina, this mother/daughter duo clash from start to finish – until AJ realises that, as her mum has always said, the world doesn’t solely revolve around her. Hartley, brilliant in everything I’ve seen her in, plays the stereotypical run-off-her-feet mother, so it was refreshing to see her glam up during the film’s final scenes.

Supported by Di Martino (seen most recently in Loki) and Smith (The Stranger), Sweetheart is a solid, confident British comedy-drama, showing off some of our up-and-coming talent. At times, a little drawn out and melodramatic – the dialogue during a face-off between AJ and Isla sounds like an argument best suited to a couple far older and deeper into their relationship – but that’s excused when we relax into how good a lead Barlow is.

A charismatic coming-of-age story, director Morrison is onto a good path if future projects follow Sweetheart‘s style.

Sweetheart, from Peccadillo Pictures, comes to DVD on 29 November. Pre-order now: https://amzn.to/3CBkq8Y and try to win a copy here!