When we think of electricity, we likely imagine energy powering our home appliances, lighting up our electronic devices, or streaking across a dark and stormy sky. Spark explains the science of electricity from a fresh, biological perspective, revealing how life at its essence is nothing if not electrical. Through vivid tales of scientists and individuals-from Benjamin Franklin to Elon Musk-Timothy Jorgensen shows how our views of electricity and the nervous system evolved in tandem, and how progress in one area enabled advancements in the other. He explains how these developments have allowed us to understand-and replicate-the ways electricity enables the body's essential functions of sight, hearing, touch, and movement. Filled with gripping adventures in scientific exploration, Spark offers an indispensable look at how electricity animates our lives from both within and without.