One At A Time tells the inspiring story of Teresa Hsu, a well-known Chinese-born Singaporean social worker. At 67 years old, Hsu founded the Home of the Aged Sick, one of the first homes for the sick elderly in Singapore, where she worked tirelessly as the matron of the home, before being made to retire from the home at 85. Following retirement, Hsu continued to care for the poor in her own capacity, such as by collecting old clothes for needy families. and founded Heart-to-Heart Service, a non-profit, informal direct-help service. Through key highlights, this short film reintroduce this icon to a new generation of online audiences, through charting her life's turning points and what shaped her relentless spirit of giving.