The most inessential and unlooked-for sequel in, arguably, the whole history of motion pictures - or anyway, since 2010's Cats & Dogs: The Revenge of Kitty Galore - Journey 2: The Mysterious Island continues the epic saga of Sean Anderson (Josh Hutcherson), the adventuresome teen introduced in 2008's Journey to the Center of the Earth, and if you were able to follow along this far, congratulations. It takes a hell of a lot to remember that Journey to the Center of the Earth ever existed in the first place: I will admit that the first time I heard of the new project, I though it was just some pointlessly snazzy hip spelling of the title, or some such bullshit. And really, why would anybody be overmuch on their toes about the impending arrival of the sequel to a movie whose chief claim to prominence is that it was one of the earliest live-action 3-D movies in the current wave, a milestone that is certainly of historical interest, and is equally certain not, at this point, reason enough to recall a film that had literally nothing else going for it besides the novelty of 3-D.

The good news first, then: Mysterious Island is a step in the right direction from Center of the Earth, owing mostly to the replacement of dough-faced Brendan Fraser as Sean's uncle by meat slab Dwayne Johnson as Sean's stepfather; it is entirely possible that in life, I overrate Johnson's skills as a comic character actor, but I don't think it's possible to be enough of a Fraser partisan to think that he's the more accomplished of the two. Remember how much more enjoyable The Mummy Returns was in the brief scenes with Johnson than in the whole bulk of the movie with Fraser? Probably not, because why in the hell would anybody devote precious synapses to storing information about The Mummy Returns?

But anyway, Mysterious Island is better, in that one respect. That is the good news, and it is the whole of the good news.

In every other regard, the new film is pretty damn mediocre, though we can flip that around: it's only mediocre, and there are many reasons why it could have been far worse than that: indeed, for the first ten minutes, it seems like it will be, thanks to some of the most fuck-you-audience exposition that I have seen in months if not years, a hellish slurry of forced ideas and unfathomably contrived leaps of logic that boil down to: Jules Verne's Mysterious Island, Jonathan Swift's Gulliver's Travels and Robert Louis Stevenson's Treasure Island were all based on one place that truly existed. Note that we already have two film-breaking questions: which of the four lands in Gulliver's Travels specifically? and is it an issue that Swift's novel does not take place in the tropics, while Treasure Island and Mysterious Island took place in two entirely different oceans? The worst thing is that it's actually possible to work out some of the answers to these questions from evidence within the film: it is both Lilliput and Brobdingnag in different ways, and it's not pirate gold that Stevenson had in mind, but a volcano of gold magma. Also, the island is Atlantis, and it rises and sinks in a 140-year cycle that turns the millennia-old structures into rubble when it does so (because of course the film takes place in the last week of the cycle), with no explanation of how they were in such good shape when we first see them. Also, Captain Nemo was totally a real person, with a real Nautilus. Also, writers Brian Gunn, Mark Gunn, and Richard Outten have obviously never, ever read The Mysterious Island, Gulliver's Travels, or Treasure Island, though they clearly did see the 1961 Mysterious Island movie with Ray Harryhausen effects, given the number of references to that movie pepper the film (of which giant bees are merely the most obvious).

So, Sean and his stepdad, Hank, go on a journey to find Sean's grandfather, which Hank hopes will get the boy to like him even a tiny bit. He expects to find nothing, but Sean, with his intimate knowledge of Jules Verne's journalistic prowess - not that the film ever trades on our knowledge of Center of the Earth because, let's face it, not even the filmmakers probably possess such knowledge - knows that there really is a mysterious island located just off of Palau, at the center of a perpetual storm system; he manages to use some of Hank's apparently inexhaustible fortune to bribe comic ethnic Gabato (Luis Guzmán, in the kind of cringing idiot role that black actors were rejecting as too demeaning back in the '40s) to take them into the heart of that storm, along with his pretty, sensible daughter Kailani (Vanessa Hudgens), and her breasts (Vanessa Hudgens's breasts). Seriously, they are framed with more loving care throughout the movie than Guzmán is. They are, in fact, onscreen almost as often as Hudgens's own face. Eventually, they crash on the island, and find Sean's grandfather Alexander, played by Michael Caine in full-on "just here for the paycheck" mode, putting as little energy or life into the movie as anything he has ever done, and looking about 10,000 years old.

Frankly, the film is too disinterested in chugging through the moldy bends of its paint-by-numbers screenplay for any of this to register; none of the actors seem to care much about what they're doing (Hutcherson in particular spends almost as much time leering at Hudgens as the camera does, and this seems to be not just his motivation for taking the part, but the beginning and end of his characterisation), though Johnson at least seems to be having a good time, possibly because he just comes across as that sort of actor who is always really excited to be in a movie, and puts the same "gee, ain't this a kick" playfulness into every single character he plays. The point, though, is not that we like or even register the human beings wandering around, but that we are dazzled by the pretty spectacle of it all; in essence, it is trying to succeed at the same game Center of the Earth was playing, except that between 2008 and now, the whole "3-D movie in a largely CGI environment full of fantastic and impossible sights" genre produced Avatar; and there are a lot of people you could describe by the phrase "he's no James Cameron", so it's not much of a criticism, but... director Brad Peyton is no James Cameron. He is, however, the man who directed Cats & Dogs: The Revenge of Kitty Galore, awesomely, which gives him perhaps the most unenviable directorial shtick in the history of cinema. It also explains why Journey 2: The Mysterious Island is so hollow and unimaginative and frankly not that interesting to look at: though it does have just enough shit that flies towards the camera to work on the intended 3-D level, and the effects are a massive improvement over its predecessor, however painfully uncomfortable Johnson looks when he's "holding" a computer-generated pygmy elephant. Nothing can explain the film's staggering disconnection from the reality of three separate adventure novels in addition to our own; I am sad to say that whatever the Gunn cousins were smoking when they whipped this thing up, it was not handed out with the ticket.