I don’t know what’s wrong with celebrities.

I don’t know why they would want to give up their multimillion dollar personalities and award-winning smiles to don unkempt facial hair and display actions only a mother could love.

Exhibit A: Joaquin Phoenix, 34

• Movies: “Walk the Line,” “Ladder 49” and “Signs”

Phoenix’s downfall is probably a long time coming. He checked himself into rehab in 2005 for alcoholism, but that isn’t the first clue behind his descent. I’m not even sure if I can pinpoint the first sign, but I am going to say a majority of his problems came when he watched his brother, River, die from a drug overdose right in front of him in 1993.

Nowadays, Phoenix is giving up his stardom for a career in rap music. Yes, that’s right: He quit acting in order to become a mediocre-at-best rapper. And he’s rocking the aforementioned facial hair, looking like the type of guy you’d find on “How to Catch a Predator.”

Beyond his looks, Phoenix has been acting like a creep recently. When he was interviewed on Letterman in February he seemed slightly impaired, and at one of his March concerts he went into the crowd to confront somebody.

Phoenix went from a good-looking movie star to a wannabe rapper who looks like the guy your mother told you to stay away from when you were little. Creepy.

Exhibit B: Macaulay Culkin, 28

• Movies: “Home Alone,” “Party Monster” and “Saved!”

Leave it to Michael Jackson’s boy toy to become a washed-up child star. Although he’s been relatively quiet recently, there was a stretch there when the guy just seemed strange.

First consider the 2003 movie “Party Monster” where Culkin plays the twisted, over-the-top Michael Alig. The drug portion of the storyline must have carried over into Culkin’s real life because in 2004 he was arrested for possession of marijuana and two other controlled substances.

Google the guy; he just looks like he’s thinking about when to make his next drug run.

If you were Michael Jackson would you want this behavior coming from your child’s godfather? I think not.

And the list goes on and on:

• Dustin Diamond – From lovable dork to wannabe porn star with no money.

• Tom Cruise – From slip-sliding around in his underwear and showing us the money to showing us the scientology and jumping on Oprah’s couch.

• The Olsen twins – From melting the hearts of people all across the world in “Full House” and their straight-to-VHS movie collection to being ridiculously skinny, alleged drug scandals and alleged relations with the late Heath Ledger.

• Lindsay Lohan – Enough said.

So what is the fascination with taking a turn for the worse? If actions like these are just a publicity stunt then I think the game should be over. I want my cute celebrities back, and I want them now.

Contact all reporter Nicole Aikens at [email protected].