Idioms Brainstorming

Barking Up The Wrong Tree

A determined dog enters frame, barking voraciously and jumping/growling/pointing at a tree. This carries on for a lengthy amount of time. A cat is revealed to be perched in a different tree a few meters away. The dog realizes (perhaps through an audio cue) that he has been "barking up the wrong tree"; he pauses, panting, and then runs towards the "correct" tree, still barking.

Steal Someone's Thunder

One character holds a jar. It contains two dark, ominous clouds, that crash against each other, producing light. The character sets the jar down on a shelf/trophy case/table, and it shakes slightly each time the clouds collide. The character leaves. A second character enters and takes the jar. Admiring it, he opens the lid ever so slightly. The jar erupts and the thunder cracks in his face.

Get your goat

Two characters interact. One begins annoying/angering/agitating the other. The agitated one communicates/says/subtitles that the other "got his goat". A small, wide-eyed goat stands up and shuffles across the table.

OR

The goat is used as a weapon. The agitated character holds it under his arm, cocks it like a shotgun, and it fires a laser from its mouth.

OR

Something equally ridiculous.