Is there anything more heartbreaking for a parent than the sudden death of a child? Can anything be more unexpectedly toxic to a marriage than that?

Jim Aina and Leslie Duval explore those questions in a brilliantly staged production of playwright David Lindsay-Abaire's Pulitzer Prize-winning drama, “;Rabbit Hole”; at Hawaii Pacific University.

Howie (Aina) and Becca (Duval) lose their 4-year-old son, Danny, when the child chased the family dog, who was chasing a squirrel, out through a gate that was usually kept locked, into traffic. Now the couple are living separate lives together in a house that was once the home to a family. At the same time, they're dealing with the efforts of Becca's mother and younger sister, Izzy, to come to terms with Danny's death as well.

Howie copes in part by playing squash with a friend. Becca fumes that the man's wife, once one of her closest friends, hasn't contacted her since Danny died. Howie goes to a therapy group to work through the experience; Becca thinks the group is a waste of time and angrily rebuffs Howie when he hints that after eight months of celibacy it would be nice to rekindle their sex life.

Mom indulges in acerbic tabloid-fueled ruminations on the “;Kennedy Curse”; and the ill-starred lives of other “;rich people.”; Izzy gets pregnant by a “;working musician”; and decides to move in with him.

Things become even more complicated when the young driver of the car that killed Danny, who was absolved of any legal responsibility for the boy's death, contacts the family as part of his own search for closure.

  Lindsay-Albaire approaches the issues obliquely. “;Rabbit Hole”; opens with Becca folding clothes while Izzy describes the hows and whys of his wife punching out a large loud drunk woman in bar. Only gradually do we notice that the clothes Becca is folding are those of a small child. Only gradually do we comprehend the bitter irony in the fact that while Becca is grieving for her child, her irresponsible sister is pregnant.

Other family secrets and conflicts also emerge in due time. All of them ring true.

Aina, last seen as C.S. Lewis in The Actors Group production of “;Shadowlands,”; is even better here in a role in which the ethnicity of the character is not an issue. Aina's eyes alone convey a broad spectrum of emotions as he plays a man struggling with his own grief and attempting to deal with his wife's grief as well. Aina's voice, expressions and body language all contribute to an excellent performance.

Duval is superb in an even more demanding role. Becca is more abrasive, and generally less likable, than her husband, but Duval makes her lighter moments believable as well. Ultimately we're rooting for her, too.

Clara Dalzell (Izzy) adds a bright splash of blonde attitude as Becca's rough-edged sister. HPU veteran Virginia Jones is a kick as the well-intentioned but overbearing mother, and HPU student Derek Elder completes the excellent cast as the sensitive young driver.

The resolution of the story feels like a considerable jump beyond everything that comes before it, but it is satisfying nonetheless.