INSIDIOUS: THE LAST KEY (15)

AS blood flows freely in the belated sequel to the 2008 horror thriller The Strangers, one victim tearfully pleads with her masked attacker to justify their desire to kill.

“Why not?” coldly responds the assailant.

Those words would surely tumble from the lips of director Johannes Roberts to explain why he felt it was necessary to return to this gruesome, blood-smeared milieu a whole decade after the original.

This film makes no pretence at originality or invention, pitting two desperate parents and their children against a trio of merciless maniacs, who conceal their true identities behind creepy masks.

It trundles relentlessly from one brutal skirmish to the next, stitching together set pieces with perfunctory scenes of family bonding.

The script is efficient but derivative. INSIDIOUS: The Last Key is a haunting too far for the spooky franchise.

The fourth and final film in the series unfolds chronologically after the events of chapter 3 and brings the terror to Elise’s front door. Lin Shaye, left, once again delivers a compelling lead performance but the plot around her creaks and groans almost as much as the floorboards of a haunted house.

■ Available from May 7 on download and streaming services, available from May 21 on DVD £19.99/Blu-ray £24.99.