"Infinite Happiness," a story in Jamel Brinkley's perceptive debut collection, "A Lucky Man," is about two men who've fallen for the same woman. One's a blithe "player" named Micah; the other, A.J., is a pensive teacher. Although A.J. is headed for heartbreak, his role in the episode yields some important realizations.

"For most people there is a gap, for some a chasm, between the way they dream themselves and the way they are seen by others," he says. "That gap might be the truest measure of one's loneliness."

Brinkley's book is packed with valuable, if disconcerting, insights. His stories, frequently set in New York City, where he grew up, often focus on introspective black male characters. Race is an important theme, but it's just one of many subjects that inspire him: He's particularly sharp on the ways in which children use fantasy to fortify themselves, and his depictions of love's many varieties are subtle and deeply observant.

"Everything the Mouth Eats," a story about estranged half-brothers from the Bronx who meet up for a martial arts conference, is a representative example of Brinkley's skill. Although his characters, Carlos and Eric, initially fail to relate, they soon realize that they should discuss their traumatic past. As boys, both were abused by their father. Ever since, older brother Eric has been haunted by "the terrible things I knew about and might have prevented." It's a harrowing tale, and it becomes even more powerful when Brinkley ends it on a hopeful note.

The book's other stories showcase Brinkley's impressive range. In one, he writes about a Brooklyn man released after serving 12 years for a drunken-driving death. The woman who died was black, but if she "had been white, Curtis knew, he would still be in prison, with many more years there ahead of him." Eventually, he moves in with a late friend's ex and her son. Curtis and Lena "wouldn't love each other," Brinkley writes, "but there was love they openly shared, and that would be enough, for now, to make a kind of family."

Another story features brothers who are navigating the contours of a tumultuous household. Omari, 11, roams about all summer in a Halloween mask, and 17-year-old Ty loves fantasy novels. With their father in prison and their mother asking them to vanish while she entertains her new boyfriend, the boys stay out till dawn, an adventure that proves terrifying and transcendently beautiful.

A Lucky Man, by Jamel Brinkley

And in the story that provides the book with its title, a frustrated middle-aged man risks his marriage by using his smartphone for seedy purposes. When his secret is nearly revealed, he tries to confess to his daughter. "He told her what he could," Brinkley writes. "He told her a lie."

With this observant book, Brinkley demonstrates an enviable capacity for narrative compression. In the space of 25 pages, he's capable of creating complex and memorable emotional worlds. This is a very hard thing to do, but in "A Lucky Man," he pulls it off in one story after the next.

Kevin Canfield is a writer and critic based in New York City.

A Lucky Man
By: Jamel Brinkley.
Publisher: Graywolf Press, 243 pages, $26.