The text explains how to use FusionAuth, a user management system, to lock user accounts when they sign in with a breached password, a feature not provided by default. It discusses configuring FusionAuth to detect compromised passwords, setting up webhooks to listen for password breach events, and using PHP to deactivate affected user accounts. The tutorial highlights the integration of webhooks to notify other systems and take further actions, such as deactivating users, notifying other services, or analyzing security violations. It emphasizes the importance of setting webhooks to ensure they succeed before processing login events, which prevents users from logging in with breached passwords. The guide also mentions customization options for user notifications and the need to secure webhooks for production use.