The cover of Sarah Crossan’s first novel for adults, “Here Is the Beehive,” gives clues about its protagonist: Here is the outline of a woman drawn with uneven lines, conjuring up motion but also anxiety.

That first impression is solidified once we get to know married and philandering protagonist Ana Kelly as she mourns the death of her longtime lover. At one point, she listens to her children singing a nursery rhyme:

“Here is the beehive.

Where are the bees?

Hidden away where nobody sees.”

As her son and daughter skip around the dining table, repeating the song over and over, while ignoring her questions and pleas, it’s clear that Ana is living those lyrics: beset by buzzing, painful worries she keeps secret.

Named Ireland’s youth laureate in 2018, Crossan’s YA novels include the award-winning “One” and “The Weight of Water.” Both are written in verse, as is “Here Is the Beehive.” Before you think “A novel in poetry? Hard pass!” give Crossan’s free verse a try. It flows as easily as honey, eliminating much of traditional narrative’s necessary blather. And it accomplishes a stream-of-consciousness feel that conveys both how quickly grief can shatter a person and how those shattered pieces still connect.

Crossan drops us right into the action. Ana, a lawyer, learns that her paramour is dead when her admin says: “I have a Mrs Taylor on the line. / She says we wrote up her husband’s will / and he’s passed. She’s very coherent.” That Mrs. Taylor, Rebecca Taylor, was married to Ana’s lover, Connor Mooney. Ana veers wildly from calling Rebecca filthy names in her head to calmly asking, “Do you know how to register the death?”

The dialogue in Ana’s head is spoken mainly to Connor: “When you wandered into my office / three years ago, / you never thought / I would have to confront your family’s grief, / or my own.” She wants to walk back through every moment of their liaison, to reminisce and to blame, to prove that she was the one Connor truly loved.

She stalks Mark, their one mutual acquaintance, to the point of lunacy. “You’re the only person who knew about us,” she pleads. “I have no one else to talk to.” Although Mark tells her to leave him alone, Ana is nowhere close to being finished with her version of things.

Some readers may experience slight confusion with Ana’s narration, because she speaks to Connor as if he’s still alive, reeling between past and present as it suits her. However, once you’ve absorbed Ana’s dilemma, you’ll understand Crossan’s purpose. Ana continues to work, to meet friends, to care for her children, to spar with her husband, Paul, all while she’s falling apart inside. Was the affair worth all that? Is any affair?

The conclusion comes as a surprise and shows Crossan to be as thoughtful a novelist for the grown-ups as she has been for young people.