This case study treats Lazarus Group as a North Korean state-sponsored actor whose operations combine social engineering, malware deployment, evasion, espionage, financial theft, and destructive disruption. It links the group's major activity classes to strategic North Korean interests, including espionage, sanctions-evasion revenue from cryptocurrency theft, and disruptive attacks such as Sony Pictures, the Bangladesh Bank heist, and WannaCry. The paper emphasizes that Lazarus campaigns exploit both human and organizational weaknesses as well as technical vulnerabilities, especially through spear phishing and other trust-based access paths. Its main defender lesson is that countering Lazarus requires security awareness, technical controls, and international cooperation rather than malware detection alone.