Glass isn’t terrible. That in itself is a small miracle. Writer-director M. Night Shyamalan went from Oscar nominee to punchline in a remarkably short space of time, largely due to his own gargantuan ego and reluctance to take constructive criticism. After Split became his first bona fide success in twelve years, there was every chance that any humility earned from his consecutive failures would disappear, leaving yet more pretentious nonsense in its wake.

Instead, we have Glass: a fittingly unconventional closer to a highly unconventional trilogy. Not only did sixteen years separate the first and second installments, but the link between the two films was tenuous to state it generously. Consequently, it was unclear how exactly the Unbreakable universe would fold into that of Split, with the final product being a story that few could have reasonably expected.

Following a brief encounter in an abandoned warehouse, David Dunn (Bruce Willis) and Kevin Crumb (James McAvoy) are detained inside Raven Hill Memorial psychiatric hospital, perhaps the most understaffed institution in the United States of America. The bewildering lack of staff is topped only by the incompetence of the few members who do bother to clock in. As a result, its hardly a surprise when chaos ensues, especially with the devious Elijah Price (Samuel L. Jackson) also residing.

Those wishing for an epic stand-off between Dunn and Crumb will inevitably be disappointed. The brief fight scenes that the duo share can essentially be boiled down to some light shoving and a couple of bear hugs. The meat of the film is instead concerned with exploring the psychology of its three leads, specifically whether their believed powers are in fact just a figment of their respective damaged minds. It’s an interesting premise, but the execution is somewhat uneven.

Some scenes fare better than others, but it’s hard to fight the feeling that Shyamalan perceives his film as far more intelligent than it actually is. Much of the psychological jargon comes courtesy of Dr. Ellie Staple (Sarah Paulson), who is so prone to smug and belittling monologues that she becomes a tiresome presence before too long. It’s a great shame because Paulson is a gifted actor, as shown by her compelling turn in The People vs. O.J. Simpson, but her performance here is wooden at best.

But, how can one talk about wooden acting without mentioning Bruce Willis? The fading star brings the same lack of enthusiasm to Glass as he has all of his recent projects, something which is embarrassingly apparent during his few action sequences. Shyamalan does his best to depict him as a genuine challenge to McAvoy’s roided adversary but no amount of movie magic is quite up to the task.

It should come as no surprise that McAvoy is this film’s most valuable player. Watching him cycle through a dozen distinct characters in the space of just one scene is genuinely impressive and there’s no doubt he elevates the material substantially. Anya Taylor-Joy also reprises her role from Split, but her character has little to do and lacks any real reason to even be there.

Despite all the dead weight, McAvoy and (to a lesser extent) Samuel L. Jackson effectively carry this film for much of its runtime. The dialogue may be somewhat stilted, but the plot remains interesting throughout and moves at a fairly good pace. Frankly, Glass was shaping up to be a fun throwaway thriller right up until the final twist which proved to be the straw that broke the camel’s back. Without giving anything away, it detracts from the overall value of the story and feels like it was included more out of obligation than necessity.

Although it’s easy to pile onto any film Shyamalan is attached to, it’s important to give credit where due. The controversial filmmaker has attempted a new spin on the saturated super-hero genre and although he isn’t entirely successful, the result is a film that is at the very least an engaging experiment. A solid score and some nice cinematography lend further credibility to the production, while the aforementioned performance from McAvoy is something to be celebrated.

Unfortunately, there are too many flaws present to give this film a meaningful recommendation, but certainly it’s nowhere near as bad as some would have you believe. Glass is a stumble on Shyamalan’s path to redemption, but one that he could easily recover from if he plays his next move more carefully.

5.5/10