The Collaborative International Dictionary of English v.0.48:

histrionics \his`tri*on"ics\, n.
   1. The histrionic art; stageplaying; acting.
      [PJC]

   2. Insincere, exaggeratedly emotional or overly dramatical
      speech or behavior performed to create an impression
      rather than as an expression of true feeling; feigned
      emotion.
      [PJC]

WordNet (r) 3.0 (2006):

histrionics
    n 1: a performance of a play [syn: theatrical performance,
         theatrical, representation, histrionics]
    2: a deliberate display of emotion for effect