Emotion can be and should be expressed as an ever changing element in your plot. How? Can I do something completely off the wall to demonstrate how easy it is??
Emotion like this in scene one.
Scene two changed like this.
Scene 3 looks like this.
Change happens to the emotions again in scene 4
Yes. It just changed again.
And change here too.
Emotions should rise and fall and change and bend and curve and mold to your characters.
Without emotional change, your character will end up looking like a cardboard cutout, which is boring and dull. How's the emotional level of your MC, beautiful guys and dolls?