Plural noun (pluralia tantum) that can take singular or plural verb agreement.
Her histrionics during the meeting were unnecessary and distracting.
Её истерика на собрании была ненужной и отвлекающей.
The actor's histrionics on stage captivated the audience.
Театральность актёра на сцене захватила зрителей.
Occurs chiefly in plural (“histrionics”) meaning exaggerated dramatic behavior; archaically, an actor.