Before entering the theater, it would probably be a good idea to curb expectations a little. Or even a whole lot.

In fact, in the case of “Journey 2: The Mysterious Island,” no ticket should be purchased without full realization as to what’s about to go down.

Let’s be honest for a moment, this is a Dwayne Johnson vehicle.

Has he managed to stumble his way into a few decent films in his career? Yes. Have any of them – especially those geared towards family audiences – contained anything beyond the most linear of cinematic experiences? Well, no.

“Journey 2” is harmless, which may actually be one of the most impressive things that can be said about this film.

Jules Verne fan Sean Anderson (Josh Hutcherson) receives a radio signal with a message in Morse code. Believing it to be a message from his remote, Verne-loving grandfather (Michael Caine) containing the location of the mythical Mysterious Island, Sean sets out to find this isle and reunite with his relative.

With the help of his clingy stepfather Hank (Dwayne “The Rock” Johnson), pilot tour guide Gabato (Luis Guzmán) and his daughter (Vanessa Hudgens), Sean is able to locate both the island and his grandfather – but his problems are only beginning.

As family fare, “Journey 2” is mediocre entertainment at best. There are some thrills, laughs and touching moments, albeit all on a small scale. Of course, audiences are also treated to a handful of nonsensical, time-filling, humorless slapstick scenes occur, but it helps that the entire cast appears to be dedicated to their respective roles.

A harmless flick could be a possible positive for some, but in this particular instance it’s a waste of time and money. The film is not good enough in terms of laughs and entertainment to appeal to an audience older than pre-teenage, and the action is foolish and cartoon-like. At the same time, the film isn’t bad enough to produce laughs or to make the audience feel as though they’ve witnessed a landmark in the history of bad cinema.

For the most part, the cinematography is beautiful. The mystique of the extensive wilderness of the island is presented in a way that makes it easy to appreciate its un-earthly aura.

The film’s special effects are one of its main downfalls. To put it short, it screams “don’t take me seriously.” Between oversized animals, a gold-spewing volcano and a colossal rainstorm, it looks as though “Journey 2” was pulled straight from a comic book with little attempt at using its visual advantages to drop jaws.

The special effects’ flatness makes it nearly impossible to take any of the film’s narrative suspense seriously. At one point, the four adventurers are pursued by a giant iguana. The unimpressive CGI and the family-friendly tone combine to create any films worst enemy: complete and unabashed cheesiness.

There are some compliments, however minor, that can be given. While the moments of tenderness, action and suspense may seem half-assed, the actors do their very best to make it all appear genuine. At the least, “Journey 2” can be looked upon as an improvement from the franchise’s original installment, “Journey to the Center of the Earth,” which was a train wreck in every sense of the word and featured a misguided performance from Brendan Fraser.

As the stepfather Hank, Johnson fills a role that he has several times before. He is able to construct a persona of someone in a bit over his head and a tad out of his element. Above all, he is able to live and learn all the while keeping his charm. If nothing else, Johnson does well playing a man of good intentions. It’s not exactly a challenging role, but it suits him fine.

Hutcherson – who has improved since the original “Journey” – holds his own and manages to create acceptable chemistry with Hudgens. Guzman is the perfect man for comic relief. The dialogue and situations don’t make for rip-roaring cinema, but his skittish-ness and overall presence makes him enjoyable to watch on-screen.

As for Caine, one might ask: Why was this role necessary? Is his career coming to an end? That’s really all that can be said, even if he was the right man to play an adventurous old grandfather. Caine put a much better spin on the grandfather role in “Secondhand Lions.”

Summing up “Journey 2” isn’t hard. It’s a movie for families that probably won’t be interesting or entertaining for anyone else.

At the same time, it is far from the worst thing to come to theaters. The film features improvements upon the original with a revamped cast that brings their own energy and dedication, and this makes the film at least somewhat worthwhile – though it’s not worth dropping money on.

Nick Coviello can be reached at [email protected].