From his first experiment growing corn in the front yard at age three, J. R. Klein pushed the envelope. Life itself was an experiment, and he held the magic wand that captured every bewitching moment. Follow Klein into his monastic journey as a Maryknoll seminarian, up the Amazon River, deep into remote areas of the rain forest, and into Nicaragua in the heat of the Iran-Contra debacle. Through it all, Klein earned a PhD in Immunology at Johns Hopkins University and worked with the world’s best scientist at the University of Pennsylvania, MIT, and The Scripps Clinic and Research Foundation. If I Could Do It All Again is a heartfelt tale of discovery, sadness, and joy.