Ghost Shark, in contrast [to "Sharknado"], is probably closer to 75 or 80 percent "great title," with the execution lagging behind. That may not be better than some on the Syfy slate, but it's better than many and there are moments of fun here, even if they come way too early in the movie and set Ghost Shark up for a final act that fizzles.
There's cheese (i.e., all Syfy flicks) and then there's cheese--Velveeta vs. Brie. But guess what? Ghost Shark is both! How victims die, which body parts are left and where, the perfectly predictable dialogue and straight-faced performances, even a historical nod to Roanoke--we're just not worthy of this much smartly executed satisfaction.
The screenplay seems more likely to have been transcribed by those guys with the plot dreamed up by an imaginative child or a drunken fanboy. Visually, the film is poorly directed sometimes to a point of such incoherence that it's not always clear what's going on, who's talking, etc. And the ending is laughably awkward.