As Rod Stewart once sang, “the first cut is the deepest”. You never forget your first love and even if you spend the rest of your life in connubial bliss there’s something about that first infatuation that cannot be replicated, or entirely recovered from.

Italian romantic drama Un Amore posits that first love is both a blessing and a curse. Alessandro and Anna meet as naive Interrailing youths in the 90s and quickly fall head over heels for one another. In the present day they are middle aged and have outwardly met many of the markers of success, but neither ever truly recovered from the relationship and they have both spent the decades since with a void in their lives that only their first love could fill.

The series cuts between the summer they met and the complicated present, where Anna (Micaela Ramazzotti in the present/Beatrice Fiorentini in the past) is married to a sweet, albeit unobservant, man called Guido, working for an environmental agency and coming to terms with her son becoming an independent adult. Meanwhile Alessandro (Stefano Accorsi in the present/Luca Santoro in the past) has flourished as an architect and lives a more footloose existence, never settling down for long enough to build a family outside his relationship with his fiery mother, Teresa. The series sees the pair reunite in Bologna after decades apart, while cutting to the first union and slowly unspooling why they parted ways.

Both storylines are elegantly performed and strikingly composed; the 90s aesthetic is precise but bathed in a rose-tinted warmth that evokes treasured memories. In contrast the present is cold and clinical; the dreary realities of adulthood have set in and drained the landscape of youthful optimism. While this makes sense conceptually, the juxtaposition is occasionally jarring, and the actors playing the past and present selves bear so little resemblance that the storylines don’t convince as different stages in the same lives.

The love between the two, though, feels lived and true. Both pairings have scintillating chemistry and a sexual frisson that is, to put it crudely, extremely hot. But beyond showcasing some romantic moments – and the bone-chilling existential horror that the choices you make as a teenager may mean that happiness can permanently slip through your fingers – this is not a love story that requires eight hour-long episodes to do it justice.

Director Francesco Lagi, best known for pitch-black comedy Missione Di Pace, seems just as enamoured by his characters as they are with each other. In both timelines he luxuriates in every steamy glance, pregnant pause and gentle caress. But at times it is hard to feel as connected to their love as the series presumes we are.

The story holds that the two have a love that defies logic, that they are linked in a way that is unencumbered by the fact that they don’t really know each other any more. The love between them is framed as impossible, tragic and near supernatural, but also that the obstacles keeping them apart are insurmountable. If we are to hold that this pair have a rare bond, that their souls ache when they are apart, then it lowers the dramatic stakes and proves frustrating that they don’t just figure this the hell out by episode two. When it has been 25 years, divorce is a perfectly socially acceptable outcome to a marriage with a sole adult child. Both sides have kept the love alive through fastidious letter writing and still make each other’s hearts skip a beat, so it’s hard not to scream at the screen for them to just figure it out.

Something truly enchanting is at Un Amore’s core: a sincere belief in love that lasts through the ages, and the deeply romantic notion that you may come across a person on a train who for ever changes your very being. But as much as their love endures, the compelling narrative wanes. This is a love that is only endlessly fascinating to those who are wrapped up in it.