What does the idiom in this text suggest?
"Speak of the devil!" Alice declared when Richard strolled into the room.

 - Alice thought Richard was a troublemaker.
 - Alice had just been speaking about Richard.
The text uses an idiom, an expression that cannot be understood literally.
The idiom speak of the devil suggests that Alice had just been speaking about Richard. People say this when the person they've just been speaking about coincidentally arrives, as if summoned.