It is not unusual for British directors to cut their teeth on slice of life drama, but few pull it off with as much warmth and care for the lives they’re putting on screen as Aki Omoshaybi, who makes an impressive feature debut with this low-key portrait of a black working-class couple in Portsmouth. It is a It’s a little rough around the edges, but Real is a deep-feeling romance, assembled on a budget of next to nothing outside the usual funding channels – Omoshaybi cast the actors by messaging them on Instagram.

The director gives a quietly convincing turn himself as Kyle, a wary man with gentle eyes who’s not long out of prison – everything he owns fits into a bin bag. When he meets Jamie (Pippa Bennett-Warner), Kyle invents another life for himself, giving her the impression that he’s a solicitor. Jamie also lies, telling him that she has an office job when actually she works part-time in a supermarket while studying accountancy and looking after her son. One night, in a restaurant neither can afford to visit, she blurts out a confession: “I just don’t want to be defined by what I do.” Kyle and Jamie see in each other the better future they hope for.

The painful question Real poses is: can their relationship survive the truth? Omoshaybi approaches the answer with patience, though his plot relies on a couple of implausible coincidences and there is a wobbly scene or two. In places the film feels a tad under-developed, and in places budgetary constraints really do show, but the understated lead performances mostly hold it together. Bennett-Warner in particular has you rooting for Jamie: damaged by a tough childhood but persistent and determined to build a good life for her son. It’s an optimistic, tender film with more authenticity in its little finger than plenty of films by more experienced directors.

• The Real is in cinemas and available on digital platforms from 11 September.