There are a few unresolved questions of the universe that stick in my craw. Among them: why people put bandanas on dogs, why Superman needs a “Supermobile” super car and how does Leonardo DiCaprio continue to get work?

After seeing Martin Scorsese’s “The Departed” last weekend, I’ve decided that Leo is the most overrated, undertalented actor working in Hollywood today.

And I’m terrified it’s only a matter of time before he ends up with an Oscar.

Some of you may say I’m just bitter because his rebellious ragamuffin with a baby face orphan schtick ruined the final season of “Growing Pains,” but I think my dislike for him goes beyond his disastrous effects on the Seaver family and Tracey Gold’s career.

Instead, the thing that annoys me about Leo is his ability to be in good movies and deliver a decent performance, without really acting.

Yet audiences fall for it – I have as well.

In “What’s Eating Gilbert Grape,” he managed to play a respectable second fiddle to Johnny Depp as the “developmentally challenged” kid with the fat mom (a must role for every “serious” actor, by the way).

Also, “Catch Me if You Can” was a light and breezy movie where the viewer could just chill and watch a boy wonder thief charm his way into money and panties like a young Danny Ocean.

But here’s the thing, “Catch Me” worked because audiences got the feeling Leo wasn’t really acting. He came across as a clever, if a little sleezy, pretty boy with a cute Cheshire cat grin, which is about how he seems in reality.

Less effectively, the same pretty boy/ milk baby Leo has made appearances in “The Man in the Iron Mask” and “Titanic” – a movie I loathed yet endured because the sentimental tripe was so beloved by the girls I knew in 1997 that hating it was akin to taking a vow of celibacy. But I digress.

Conversely, the other side of Leo is the bad-boy. Presumably, this is the dark side, the one where audiences don’t know if they’ll like his character or not, although they are eventually supposed to.

This is the Leo seen most recently in “Gangs of New York” and a little bit of in “The Aviator,” as well as in the upcoming “Blood Diamond.”

The other side of Leo is generally accompanied by a lousy accent, a lot of squinting and really bad facial hair (think grammar school play where dyed cotton balls are pasted on a little girl’s face).

That’s what really disappoints me about “The Departed”; he’s working for Martin Scorsese, and is giving yet another “dark Leo” performance – this time with a Boston accent.

If Leo is the new muse of one of the top five directors alive right now (and probably one the top 15-20 directors of all time), can’t moviegoers expect more than a cookie cutter portrayal seen plenty before?

Leonardo DiCaprio may be the definition of the modern leading man, but where are the many layers of great actors like Robert DeNiro? Even younger leading man Edward Norton crafts unique characters with every film. But not Leo.

And based on the unrestrained laughter in the theater during the “Blood Diamond” trailer – in which he plays a South African mercernary with (you guessed it) bad facial hair and a lousy accent – maybe audiences have had enough of the pretty boy Leo vs. dark Leo show.

We can only hope.