Of all the truths lodged in Tessa Hadley's latest novel — and there are many, although this splendid, perceptive book is never sanctimonious — the most honest is startling yet simple. "You could not have everything," one character realizes. "The whole wisdom of life amounted to that. Whatever you had was instead of something else."

Nothing is certain, the adage goes, but death and taxes. "Late in the Day" changes and expands on that famous idiom: What's inevitable are death and choices. Whatever you have, it's instead of something else. This is most apparent when you're well into middle age, living blithely with the decisions you've made, and then a cataclysm thumps you hard into the unwelcome understanding that everything is fragile, and everything is temporary.

In "Late in the Day," the tragedy befalling a quartet of longtime friends is the death of one of them. Zachary, an affable, 50-something London art dealer, drops dead mid-conversation at his gallery. Left behind are his distraught wife, Lydia; his college student daughter, Grace; and the couple's best friends, Alex and Christine.

"Of all of us," thinks the stricken Christine, an artist who flourished under Zachary's praise, "he's the one we couldn't afford to lose."

She may be right. Everyone is reeling. Christine finds herself unwilling to sleep with her husband and unable to continue her work. A stoic, moody poet with only one published volume, Alex discovers a longing to renew his erotic life. And with no career and daughter Grace living in Glasgow, Lydia is lost: "I don't know how I'm going to fill my days!" She soon finds a way to fill her time — and upsets the delicate balance remaining.

Hadley has expertly examined the complications and intimacies of marriage and family in such novels as "The Past," "The Master Bedroom" and "Clever Girl." In "Late in the Day" she continues her persistent exploration of human frailty and resilience, moving easily between the present and the past to reveal the hard edges and silent compromises that shape all relationships.

A surprised Zachary realizes, for example, that his best friend is indifferent to Christine's art. "He hadn't known that Alex didn't take his wife's work quite seriously: didn't, in their horrible old schoolboy phrase, really rate it. He must have only been kind, and condescending, and keeping a domestic peace."

Keeping that peace isn't always possible, at least not for the survivors in "Late in the Day." But with compassion and insight, Hadley raises the possibility of hope for these wonderfully imperfect characters. Even after the unthinkable, they — and we — may stumble upon what we need.

Connie Ogle is a writer and book critic in Florida.

Late in the Day
By: Tessa Hadley.
Publisher: Harper, 273 pages, $26.99.
Event: In conversation with Curtis Sittenfeld, 7 p.m. Jan. 24, Magers & Quinn, 3038 Hennepin Av. S., Mpls. Sponsored by Rain Taxi.