Establishing a spooky setting is half the battle when crafting a scary movie. So in that respect, “Ghost Ship” offers smooth sailing for horror fans.

The vessel of the title refers to the Antonia Graza, an Italian ocean liner that has been adrift in the Bering Sea for 40 years. An American team from a salvage tugboat stumbles across the behemoth, and boards it in hopes of claiming whatever spoils can be discovered. They find the opulence of the ship’s former existence in decay, and it has turned into a rusted, hazardous hulk, haunted by the events that claimed the lives of its passengers and crew.

“Ghost Ship” capitalizes on some truly creepy art direction and production design. This floating mausoleum is a fine place to situate a haunted house movie.

Unfortunately, once a spooky setting is built there needs to be something interesting going on, and this film is slowly sunk by the weight of an inferior script.

When it isn’t ripping off better movies (“The Shining,” “Dead Calm,” “Deep Rising”) or worse ones (“Event Horizon”), it’s tacking on plot elements that seem unnecessary (maggots anyone?) and introducing a villain whose powers are never fully explained. Not to mention all the problems with the principals of the tugboat Arctic Warrior.

The salvage crew is led by reliable Irish actor Gabriel Byrne, who brings a weathered weariness to all his roles. He’s perfect as a sea captain with an alcoholic past, though the filmmakers never do anything with the fact that he begins drinking again  prompted by the ghost of a fellow sea captain, no less. And his fate takes place off-screen, which is a rather lame finale for such a pivotal character.

Julianna Marguiles takes the Sigourney Weaver role as the salvage team leader. She may not be a very physically imposing actress, given that she supposedly has the most dangerous job on the ship, but she comfortably steps into the hero gig. Surprisingly, it’s when the “ER” veteran needs to show a little emotional range that she barely treads water.

Other seasoned actors such as Isaiah Washington, Ron Eldard and Karl Munder make up key members of the unit. They all bring at least a touch of respectability to characters that are primarily designed for one reason: to meet with bloody demises.

Aside from a very startling intro that foreshadows the fate of the Italian ship’s crew, the mounting violence and gory special effects become a distraction. So are the jarring rock-video edits and pounding techno beats thrown in by director Steve Beck, the same culprit behind the recent remake of “Thirteen Ghosts.”

While an improvement over Beck’s previous effort, “Ghost Ship” progressively loses its impact just as soon as the phantoms begin interacting with the boarding party. For the first 20 minutes when the team is exploring the carcass of the Antonia Graza, there is a palpable sense of foreboding and mystery.

“I think I saw something I couldn’t possibly have seen,” Margulies tells a doubting colleague.

Once it’s clear what she has seen  and these apparitions start revealing the details of the mysteries through more expository dialogue than a James Bond villain  the movie turns into a special effects centerpiece of morphing faces and relentless explosions.

Remember, special effects aren’t scary  cool and sometimes thrilling, maybe, but never scary. The fear of the unknown is a much more blood-curdling proposition.

Once a horror flick succumbs to digitally created images, it’s similar to shining a bright light into a dark corner.