drive-by-spy

When you discretely drive by a past or current boyfriend/girlfriends house to see if their car is there and if they are home. Or to see what other cars are in the driveway to determine if anyone else is with them.

It's Saturday night and Joe didn't ask me to spend the evening with him. I think he may have a date with someone else! I'm gonna do a drive-by-spy and check out the scene.

drive spy

passing by someone or something several times in fear of being caught or without being noticed

We took a drive spy by his house today.