Robin Thicke used to rock a "Jesus perm".

The suave singer has hit the number one spot in over 50 different countries with his track Blurred Lines, which also features T.I. and Pharrell.

Prior to the smash hit, Robin had success on a smaller scale with songs such as When I Get You Alone, but his image wasn't quite as cool as it is now.

"I had the long hair! Well, the funny thing was, I had always written and produced for others but I didn't devote time to my own music and I told myself I wouldn't cut my hair until I hear my own song on the radio," he laughed to Australian radio hosts Kyle and Jackie O.

"That took about two years, so I ended up with this Jesus perm! There was no style, just a big, flowing head of hair."

Blurred Lines has two music videos - a tame version and an X-rated one, where the girls featured dance around topless.

Robin revealed how the promo came about and joked they had no money left for exciting stunts after paying the gorgeous women.

"Honestly, it was all the director's idea! I told her I just wanted to make a funny or silly video and she said, 'Well, what if the girls take their clothes off?'" he explained.

"They were well paid! That's why the rest of us are just standing in front of a white wall; because all the money went to the girls' boobs! There's Treats! Magazine, it's a fashion magazine, but it's predominantly nude and Emily [Ratajkowski, girl from the video] was on the cover and star of the magazine and I gave it to the director as an idea, but she just got the girl!"

Robin is married to actress Paula Patton and they have a son, Julian, together.

Luckily, his wife is relaxed about his saucy music promo.

"I've been with the same woman since we were teenagers. She is extremely cool with it, she's a very talented, amazing woman," he smiled.