Dermot Mulroney‚ÄĒnot Dylan McDermott‚ÄĒhas signed on to star in the next chapter of the¬†Insidious¬†franchise.¬†Mulroney will join previously¬†announced¬†star¬†Stefanie Scott (who‚Äôs also set to play¬†Jem‚Äôs sister in the upcoming¬†Jem And The Holograms).¬†The first two¬†films centered on parents Patrick Wilson and Rose Byrne and their comatose/possessed child, but the third appears to be set in a whole new¬†traumatized¬†household.¬†Screenwriter¬†Leigh Whannell will return to pen¬†the third installment and also¬†make his directorial debut.¬†According to¬†Deadline,¬†plot and character details are being kept under wraps. Filming begins July 7 with an eye towards an April 2015 release date.