For an action flick that starts to sink right out of port, “Battleship” does take a clever turn. But, boy, do you have to wait a long time for it to smarten up.

First, at least a solid hour goes by before you see an alien. Why, you may ask? Because the script is intent on making you understand that the lead character is such a loser.

Taylor Kitsch (“John Carter”) is Alex, and Alexander Skarsgard is his brother, Stone. To impress a pretty girl who walks into a bar when the kitchen is closed, Alex breaks into a convenience store to steal a chicken burrito for her. A chase scene involving police officers ensues.

Now, some time later, Alex and Stone are both in the Navy. The admiral (Liam Neeson) is the father of the girl (Brooklyn Decker), who is now in love with Alex. He plans to ask the admiral for his daughter’s hand in marriage, but Alex is afraid to follow through.

This takes a long, long time to set up — a lot longer than you’d ever expect. Finally, though, “something” shows up near Hawaii, and that is a Transformer …er, I mean, an alien ship. And, boy, are they ever out to destroy everything they can. Many people are killed — so many that Alex ends up commanding a ship. His girlfriend, meanwhile, is elsewhere, hiking with a disabled veteran (Gregory D. Gadson), and ends up being trapped while the rest of the world goes to war.

You know the movie may not have a lot of depth when the first thing you see is the logo of the Hasbro toy company, the creator of the Battleship game that has entertained so many generations.

I have to admit it’s fun to see singer Rihanna here, giving it her all as one of the sailors. But you have to wait a long, long time for the movie to become interesting. When it does, it becomes smart and even inspirational for a few minutes as it salutes older veterans in a scene I’d like to see again.

But the rest of the movie is inconsequential. Sci-fi fans will be disappointed with the aliens, which could have come straight from the Syfy television network.

This is worth a matinee or a rental. As for spending your hard-earned bucks to see it in a theater, you’d be wise to steer clear.