Everyone thinks 33-year-old travel writer Reannon Muth is brave for backpacking through dozens of countries on her own. But what Reannon's friends, travel blog readers, and boyfriend don't know is Reannon has an anxiety disorder that makes it difficult for her to get close to people. She's afraid to ask for help, she's afraid to be vulnerable, but most of all, she's afraid to be herself. When Reannon suffers a surprising loss, her fearless façade begins to crumble, and she decides to hike Mount Whitney—the tallest mountain in the contiguous US. But as she embarks on her biggest adventure yet, Reannon realizes if she has any hope of healing, she must face her fears or risk losing everything, including her one chance at real love.