A playwright who has written a one-act farce, Erin Lavik has a day job that is no laughing matter. She uses polymers and neural stem cells to promote recovery from spinal cord injuries, which 10,000 people suffer each year in the United States alone. A Yale University assistant professor of biomedical engineering, Lavik designed polymer scaffolds that mimic the architecture of a healthy spinal cord, seeded the scaffolds with neural stem cells, and implanted them in paralyzed rats. Much to everyone’s surprise, the rats were able to move their limbs, bear weight, and even walk. Although spinal cord injury research is a big field, Lavik’s method is the first to demonstrate such dramatic success. Repairing spinal cord injuries in humans will be a bigger challenge, but them, Lavik didn’t expect her injured rats to walk so soon. If she has her way, people with spinal cord injuries could be walking sooner than expected, too.