Aspiring crime writer Dinah Laurel Lance moves back to her hometown of Star City after a treacherous stint as a criminal defense attorney, inspired by her long-missing passionate journalist younger sister Sara and urged by their loving police captain father, to start making a new and different life for herself. She starts going by her desired pen name of using only her middle name, and starts on a hopeful but desperate novelization of her sister’s and ex-boyfriend’s disappearance and assumed deaths.
It’s hard to feel comfortable, even though she knows that for her own sake - and maybe, for others’, too - she needs to write the story; but one particular coffee shop offers a homey enough feeling, and wonderful enough hours, that she starts finding her place at a table in a corner there.
Part-time shop manager and barista Thea Queen can’t help feeling like she knows her newest - and cutest - regular from somewhere, but soon wonders if the extent to which she likes Laurel is clouding her memory with a crush. She falls, hard, but she keeps her cool long enough, especially as Laurel is gratefully accepting of any kind gestures of hers - croissants set down at her small table before she arrives in the morning, lattes prepared before she even reaches the front of the line on slow days, a couple free cookies, and eventually working up her courage to properly ask what Laurel’s book is about. Thea listens intently, only to notice similarities with what narrative she has of her older brother’s disappearance, and soon they discover that Thea’s brother Oliver is the ex-boyfriend of Laurel’s who mysteriously went missing with her sister years ago.
In writing and researching and reminiscing, the two only grow closer and closer, so when Laurel’s freelance journalism and hit-and-miss magazine submissions start failing to cover rent and other basics, asking Thea to move in with her makes more sense than turning to her father for any more monetary support. With a city falling further into the cold grips of crime, he has more than enough on his hands as Chief of Police; besides, Laurel even lives closest to her favorite coffee-focused haunt, and her apartment is nicer and safer than Thea’s own.
It is still, however, a one-bedroom apartment...which turns out to be slightly less of a problem than expected. At least, in terms of sharing space - even, eventually, sharing a bed, because it doesn't make sense to pay for late night texting or Skype when Thea's only a room away from Laurel's room.
But then, when Oliver makes it back to Star City, alive, kicking, and taking on a gig as a masked vigilante, their barely settled status quo flips upside down, and suddenly, their world gets a lot bigger than their coffee shop: aspiring crime writer becomes aspiring crime fighter, part-time barista becomes her part-time backup, and mutually enamored friends become fiery, intense lovers. Lovers with missions, at that - who just might solve some of their city's biggest mysteries, and save the city itself, on the way to becoming one of the most powerful couples in all of North America.