USA Today and International Bestselling Author Jenifer Ruff writes dark and twisty mysteries and medical thrillers in three series: The Agent Victoria Heslin series, The Brooke Walton Series, and The FBI & CDC Thriller series. Her novels showcase contemporary issues and bring complicated characters to life. An avid fitness enthusiast and hiker with a background in epidemiology and public health, Jenifer lives in Charlotte, NC with her family and a pack of greyhounds. Sign up for her Reader's Newsletter at and never miss a new release.

Jenifer Ruff

USA Today, International Bestselling Author

Only Wrong Once

A remarkable look at the efforts and sacrifices that shield us from terror.

A sinister experiment in Aleppo.
Two mysterious deaths: one in LA, one in Boston, each with the same horrific symptoms.

In Los Angeles, FBI counterterrorism agent Quinn Traynor receives an urgent call from CDC agent, Madeline Hamilton. She's discovered the first victim of a lethal, unfamiliar virus. Their joint investigation uncovers an imminent bio-terror attack and their only hope is to identify the terrorists carrying the disease. With just two days remaining before it's too late, the FBI and the CDC race to prevent a pandemic. The ensuing nightmare will hit closer to home than they ever anticipated and one of them will pay an unimaginable price for protecting their country.

Only Wrong Once is the first book in the phenomenal FBI and CDC Thriller series from USA Today and International Bestselling Author Jenifer Ruff.

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