Is there anything worse than running into an ex?

Yes: running into them every day because you've accidentally moved into the flat above them!

This is exactly what happens when Diana (Zosia Mamet) returns to Brooklyn after studying abroad for three years. She's keen to pursue her dream of becoming a writer but instead finds herself selling wedding dresses to bimbo brides - and with no place to live. That is until she moves into a perfect apartment owned by artsy widow Amy (Deirdre O'Connell). Well, it's perfect until she discovers her ex-boyfriend Ben (Matthew Shear) is living in the basement.

While Diana wants to salvage a friendship from the ruins, Ben is still sore about being dumped and wants nothing more to do with her. Their past is explored through (500) Days of Summer/Eternal Sunshine of the Spotless Mind style flashbacks which are interspersed throughout the present-day story, but unlike the captivating but imperfect relationships examined in the former two examples, Diana and Ben's teenage fling is a total flop.

By no means is this Mamet's doing. The Girls star commands the screen and delivers a funny yet vulnerable portrayal of somebody who - much like her former character Shoshanna Shapiro - has pros and cons but is ultimately relatable and likeable.

Shear's performance is less inspiring but he'd be hard pressed to bring much to a character as boring as Ben. Flashbacks to cheesy dates and cuddles in bed do nothing to answer that niggling question: what on earth does Diana see in this guy?

What's more, a script by writer and director Sophie Brooks leaves no room for natural communication.

Diana and Ben are incapable of having a conversation that omits sarcasm or self-deprecation, and constantly second-guess what the other is going to say so they can top it with an even more deadpan quip. Apart from one humorous exchange about lemons, it is excruciatingly awkward watching these former flames interact.

Luckily, The Boy Downstairs fares far better when it comes to the film's female relationships.

The unexpected intergenerational friendship between Diana and her landlady Amy goes from strength to strength as the plot progresses, with the duo performing aerobics together one minute and crying over a stiff drink the next. Meanwhile, Diana's pal Gabby (Diana Irvine) is the best friend every girl wants - who gets extra points for telling her non-committal lover where to stick it, and also devouring a plate of spaghetti and meatballs on a casual walk through Central Park.

Even love rival Meg (Sarah Ramos) brings some gloriously sassy conflict when she squares up against Diana, and together the pair create some of the feature's most laugh out loud instances.

All in all, it's a shame that Brooks didn't play to The Boy Downstairs' strengths. Prioritising the love between the well-written women would have proved to be a far more satisfying watch than an insipid failed romance plot.