If Instagram-style effects could be applied to film, the result might well resemble the opening sequence of the golden-hued Strawberry Fields. This warm and arty beginning, however, belies the subsequent bleak exploration of difficult subject-matter: the consuming nature of mental illness and its effect on other people.

Following a chance encounter, Gillian (Anna Madeley) creates an alias and becomes a strawberry picker in rural Kent in an attempt to escape her demons. The isolated setting promises retreat until Gillian’s mentally ill sister, Emily (Christine Bottomley), arrives and Gillian is forced to confront precisely what she is running away from. The film centres on the problematic relationship between the two sisters as the balance of power shifts, drawing other strawberry-pickers, most notably enigmatic hunk Kev (Emun Elliott), into the web of manipulation, lies and violence.

For a low-budget venture emerging from Film London’s Microwave project, Strawberry Fields is sumptuously shot, but still feels fully grounded in its natural setting. The shots switch fluidly between sunny landscape vistas and the squalor of the workers’ caravan accommodation or overcast coastal scenes, visually reflecting Gillian’s shifting moods. Just when she feels able to relax and enjoy Kev’s company, Emily’s presence threatens to ruin this peace, darkening the atmosphere in a way reminiscent of A Streetcar Named Desire.

The three lead actors convincingly portray the troubled natures of their respective characters, with Madeley standing out as perfect in the role of the sexually unsure and introspective, yet inherently strong, Gillian. The film only deals obliquely with the past and future of its protagonists and firmly puts the audience into the present moment, giving us a sense of immediacy. Though the characters are believable, they are not particularly likeable and are difficult to empathise with. Both sisters are prone to lying and mood swings, although Emily comes off as the weaker and more manipulative of these two diametrically opposed sisters. In contrast to the heavily contrived one-liners of Hollywood, here we have dialogue that is mundane and strikingly blunt ("I just tried to kill you").

One of the most effective features of Strawberry Fields is its emotional realism and refusal to descend into soppiness. It is also ambiguous in its portrayal of mental illness and leaves the viewer free to decide where their sympathies lie. Since we experience events from Gillian’s point of view, we understand her desire to escape her familial responsibilities and pressures. Emily’s condition is neither excused nor ridiculed in the film; rather, it is starkly displayed for us to judge. We see it as the people around her see it, appreciating the full unpredictability of her condition.

Don’t be tricked by the romantic-sounding title into thinking that Strawberry Fields will offer a light-hearted Arcadian jaunt. What it does offer is a hard-hitting depiction of people’s messy lives and relationships as they really happen. While it was often stark and uncomfortable to watch, this is a well-constructed independent film brimming with cinematic honesty.