In this delightfully charming and heartfelt debut love story, two lonely and wildly different strangers embark on a short-term friendship over one London summer—only to discover they may be something more by the time the season ends.

No one would ever call Ava Monroe a people person, which isn’t ideal for a barista in a busy London coffee shop. She’s sarcastic, blunt, and set in her ways, with a rule that her relationships are to be strictly no-strings-attached. But now, rather inconveniently, her best friend, Josie, is about to leave for several months, and she's pushing Ava to get out of her comfort zone and meet new people—though Ava's really not keen to shake up her life.

Then the interminably cheerful and undeniably gorgeous Finn O’Callaghan rolls into her coffee shop with an unusual proposal: a strictly friends-only summer fling. Finn needs a local to help him complete his London bucket list before he moves away, and Ava needs to reassure Josie—and maybe herself—that she won't be lonely. Besides, it’s only for a few months: What's the worst that could happen?

Before long, their mismatched friendship of convenience becomes more tolerable than Ava expected. As they work their way through Finn’s list around the sun-drenched city, from rooftops and floating bars to nights at the museum, their adventures—and Finn’s company—start to feel . . . nice. Incredibly, terrifyingly, dangerously nice.

Still, rules are rules—and Ava's not one to make exceptions. As the days get shorter and Finn’s departure gets closer, Ava is surprised to find herself soaking up every moment, wishing they had more time together.

But that’s the thing about summer: it always ends. Right?