The Dreadful Scene

From Guidevines

A term in theatre for a scene at the beginning of the play where two characters (classically, two house servants) discuss what has been happening simply in order to give the audience background. Actors dread it like all hell, because basically it's a lecture, slow, and not interesting. Writers should avoid it, instead finding a dramatic scene in which necessary pieces can be woven in.

The Dreadful Scene is a form of infodump.

A classic Dreadful Scene in fiction is the opening of The Silver Wolf by Alice Borchardt.