Eye-in-the-sky noun phrase informal
Surveillance above your head or in the sky, such as a camera or a police helicopter
The eye-in-the-sky in the store can prove that I didn't steal your phone.
Eyes-in-the-sky have helped the police a lot in solving cases.
To do domething based on your emotions rather than for rational reasons
I can't believe that Tom beat his classmate. He's always the one who let his heart rule his head.