Shen Changsheng, a traditional Chinese medicine practitioner who sets up his stall beneath an old locust tree, carries the burden of a decades-old wrongful conviction involving his master, Gu Lingyun. Guarding his pouch of silver needles, he treats the local residents while secretly investigating the truth behind the old case. Even when framed and suppressed by villains, threatened and having his stall smashed, he refuses to back down. Joining forces with a journalist, a veteran detective, and an old friend, he uses a new case involving counterfeit medicine to reopen the long-buried investigation. Ultimately, he brings the mastermind, Xie Wuqiong, to justice, clears his master's name, and sets the record straight. Three copper coins preserve his original resolve, while a lineage of acupuncture techniques carries on his master's noble spirit. With the injustice finally overturned, he stays in the old neighborhood with his beloved, passing the benevolent heart of a healer down to the next generation.