The idiom “speak of the devil" is used when you're talking about someone, and that person unexpectedly appears or is mentioned in the conversation.
It's often said in a light-hearted or joking manner.
Meaning of ‘Speak of the devil’ Idiom in English
Speak of the devil
Meaning
Examples
Speak of the devil, here comes Alex.
Speak of the devil, Sarah just added me on Facebook.
Speak of the devil, there's a new Stephen King book coming out!
