The deadly hantavirus has killed dozens of Native Americans, so when a reputable pharmaceutical company claims to have developed a vaccine against the deadly disease, it should be good news. But when ImmuVac asks Dr. Isabel McLain to conduct a clinical trial of the vaccine on the Blackfeet reservation in Browning, Montana, the proposal gets a decidedly mixed reaction from her and from the suspicious Blackfeet. Is the new drug truly safe, or are the Blackfeet being used as human guinea pigs?

Indian activist Monty Four Bear fears the worst, but Dr. McLain decides to stake her reputation on the trial's safety. Having taken over the poorly funded reservation clinic after the catastrophic failure of her marriage, Isabel has fought a long, hard struggle to gain the trust of the wary Blackfeet residents of the reservation. She knows she risks everything she's accomplished by endorsing ImmuVac's clinical trial, but she's willing to take that chance if it means developing a weapon against the hantavirus.

But when corporate greed makes for questionable science, whom can Isabel truly trust with her life and her career--and the lives of the Blackfeet?

"Not since Robin Cook has the medical thriller been this tense and exciting . . .good late-night reading."
- Knight Ridder News Service

"A deftly woven thriller . . .substantial and intriguing."
- Library Journal

"Guaranteed to make any reader late for dinner, or even breakfast."
- Booklist

"Christofferson's smooth plotting and prose show the dexterity of a novelist coming into her own. She's especially good with her large cast of Blackfoot characters."
-Publishers Weekly

"Powerful."
-Midwest Book Review