I might as well come come straight to the point: The Con Artists by Luke Healy is my favourite graphic novel of the year so far, and to be honest, it might just be among my favourite comics ever. I’ve already read it twice, yet still I feel that I could go back to it again some time quite soon. Healy is one of those very noticing artists, and the great pleasure of his deeply satisfying fourth book, which is about an old friendship that will shortly curdle, lies in small things: little details you may not notice the first time around; ambiguities that nag away at you. Then again, even on a first reading, it’s a stand-out: so funny and melancholy, so knowing and true. Frank and Giorgio, the two men at the heart of it, are brilliant, vivid creations, and the passive-aggressive scratchiness between them is so beautifully observed. It isn’t hard at all to imagine such frenemies as the stars of some future film or TV series, though personally I would be quite content if Healy would only give them another outing between hard covers.

Frank (the standup comedian who is the book’s narrator) and Giorgio were friends as children, and on paper they’re very similar: both Irish in London, both gay and both single. But in adulthood, they’re not especially close, meeting up only every few months or so – until, one day, Giorgio calls Frank and tells him he has been hit by a bus. His wrist is broken. Could Frank look after him when he gets home? It’s worried Frank, not Giorgio, who asks this question, but almost immediately he begins to regret the offer. Giorgio is a nightmare patient, as demanding as a hotel guest, for all that it’s in his house that they’re staying. It’s almost sinister, the way he insists that Frank washes his hair or cuts up his dinner – and there’s something else, too. How is he making a living? In the bathroom, the soap is flashy – Frank would have to play three gigs to buy it – but his friend is getting letters from the benefits office. Nothing makes any sense, and trying to work it all out triggers Frank’s already quite bad anxiety.

Popular culture is overly populated with depictions of fraudsters and grifters right now, from Elizabeth Holmes, the biotech “entrepreneur”, to the so-called Tinder Swindler, Simon Leviev – an obsession born, perhaps, of the fact that social media makes some cons so much easier to pull off; that each and every one of us has at some point fallen for an Instagram lie. Healy’s book speaks to this mood, I think; Frank will come to wonder if he knows his friend at all. But it’s a tender, intimate story, too, one in which long-repressed love and competitiveness bubble up as if from nowhere. I love the way Healy writes, his characters so ineffably droll, and their speech always so spare, and I love the way he draws, too – just enough detail in every frame to transmit character, mood, imminent jeopardy (it’s there in a shrug or a yell, the way they carry a bag or arrange themselves on a sofa). He can be hilarious, and if you are even slightly tired of the current craze elsewhere in the literary world for thinly disguised autobiography (out of which, having cleverly given one of his characters a false moustache, he gently takes the piss), then I think this minor masterpiece of a book might be for you.

• The Con Artists by Luke Healy is published by Faber (£16.99). To support the Guardian and Observer order your copy at guardianbookshop.com. Delivery charges may apply