One-man franchise factory James Wan (‘Saw’, ‘The Conjuring’, ‘Annabelle’) somehow stretched ‘Insidious’ into four films. Unfortunately, he’s rarely involved in his own sequels. ‘Insidious: The Last Key’ really could have used his talents to squeeze out some more scares… or the presence of anyone who cares about anything in this franchise beyond its almost inexplicable profitability.

Long ago, ‘Insidious’ was a haunted house movie (and unofficial ‘Poltergeist’ remake) about a family being chased by things that go bump in the night. Now, the heroes are the people you call when there are bumps keeping you up at night. Long-time character actress (and Farrelly brothers regular) Lin Shaye returns as Elise, the conduit with psychic connections to the afterlife (referred to as “The Further” in ‘Insidious’ lore). She also has a pair of geeky, bumbling, ghostbusting buddies played by Angus Sampson and series screenwriter Leigh Whannell. Once again, they’re called upon to investigate some spooky shenanigans.

This time, the shenanigans in question involve Elise’s past, taking us via flashback to the 1950s, when her family lived so close to a prison that the lights would flicker whenever some pour soul got the electric chair. Elise (played by Hana Hayes as a youngster) was struck by her gift in these early days, sketching the recently deceased and spouting off facts about their last days on Earth. This enraged her alcoholic father, and at times it seems like the movie might be an interesting exploration of supernatural powers spurned out of domestic abuse. Not for long, though. This is still a dumb ‘Insidious’ sequel, so the focus is on jump-scares and the occasional giggle.

Chronologically, this flick is designed to connect the prequel of ‘Chapter 3’ with the original film (while also obviously setting up further sequels). There’s a certain goofy charm to watching Elise and her gang of ghostbusting buddies play Scooby-Doo. The plot is as convoluted and yet also as slight as always. The central trio are fairly charming and Hayes is surprisingly moving in the flashback material, but for the most part acting wavers between amateur and barely competent – not that story or performance was ever particularly a strength of the ‘Insidious’ series. However, now that this franchise has essentially become a bumbling buddy picture with little ghosties getting the buds together, it’s an increasing distracting to notice how false and wooden everything feels.

Of course, anyone buying a ticket for ‘Insidious 4: The Most Recent One’ isn’t there for some sort of complex exploration of the human condition. This is all about jumps and leaps and loud noises and creepy creeps. Sadly, that stuff isn’t particularly great either. Director Adam Robitel (‘The Taking of Deborah Logan’) isn’t as skilled a stylist as James Wan. The Italian giallo surrealistic extremes that made the first films in the series so memorable are long gone. That’s due to talent not being as singular behind the camera, dwindling budgets and, more than anything else, repetition. The jumps, demons, and surreal afterlife are all too familiar to register now. Everyone involved does their best to keep the franchise alive, but it’s all for nothing. You can only scare audiences and get laughs with the same gags for so long.

Three sequels down the line, the ‘Insidious’ toolkit is just a little to worn out to do anyone any good. The scariest part of this mediocre horror fourquel is imagining how painful it would feel to suffer through a fifth chapter.