You are a SOC analyst at an organization that uses Google Security Operations (SecOps). You are investigating suspicious activity in your organization's environment. Alerts in Google SecOps indicate repeated PowerShell activity on a set of endpoints. Outbound connections are made to a domain that does not appear in your threat intelligence feeds. The activity occurs across multiple systems and user accounts. You need to search across impacted systems and user identities to identify the malicious user and understand the scope of the compromise. What should you do?