Financial crime rarely appears in isolated records; it emerges through networks of entities, relationships, and behaviours over time. This article explains why financial crime graphs must be treated as foundational, temporal structures anchored near the Bronze layer of a regulated data platform. It explores how relationships are inferred, versioned, and governed, why “known then” versus “known now” matters, and how poorly designed graphs undermine regulatory defensibility. Done correctly, crime graphs provide explainable, rebuildable network intelligence that stands up to scrutiny years later.