A doctor’s religious doubt is shaken by a transplant patient’s eerie knowledge of his organ donor’s most intimate secret.

Doctors tend to the needs of their patients, but patients give meaning to the lives of their doctors. So it is for Cullen Brodie, a twice-divorced California nephrologist, and Ennis Willoughby, a troubled cross-dresser whose life is saved by a rare heart-and-kidney transplant.

Cullen’s bitter disbelief in the afterlife is tested when Ennis begins to exhibit tastes and characteristics uncannily similar to those of his female organ donor - whose first name Ennis inexplicably knows. When Ennis becomes convinced that the donor’s soul has inhabited him, Cullen sides with Ennis’s psychiatrist, who tells Ennis he has subconsciously confused his emerging transgender personality with the imagined characteristics of his female donor.

While his psychiatrist coaxes forth Ennis’s female side, Cullen is summoned to the South Pacific by an old lover for a reckoning of their past. On the island paradise of Rarotonga, he is forced to confront the heartrending truth about a tragedy that destroyed their college romance - a tragedy Cullen blames on religious zealotry.

Filled with resentment over what he has learned, Cullen returns to Southern California determined to shatter Ennis’s delusion of ensoulment. But Ennis’s eerie knowledge of his donor’s greatest secret forces Cullen to consider the unimaginable: Is it possible he is witness to a verifiable incident of transmigration, tangible proof of a human soul? Or is he witness instead to the miracle of being transgender? Male and female at once, the glory of one and the glory of the other, both shining - like a parrotfish, another miracle of nature, changing gender apace, beside its glorious, ever-changing hue.