Community worker Lin Xi opens a public welfare science popularization classroom, teaming up with community doctor Xiao Zhou to popularize anti-fraud, safe medication, and first-aid knowledge for the elderly in their jurisdiction. Retired accountant Master Chen listens and learns attentively, shifting from listening passively to actively spreading knowledge, driving neighbors to raise their awareness of precautions. Bit by bit, glimmer converges into warmth, and the science popularization classroom walks into thousands of households, guarding the safe lives of the elderly group.