(one's) eyes are popping out of (one's) head(redirected from their eyes were popping out of their heads)
(one's) eyes are popping out of (one's) head
One's facial expression indicates surprise or extreme interest in what one is looking at. My eyes practically were popping out of my head when I saw that my parents had bought me a car for my birthday! Stare much? Your eyes were popping out of your head when that guy walked past us.