I got a letter just the other day
She sent a picture but she didn't sign her name
She wore high heels and a little black lace
I knew her body but I couldn't see her face

She didn't leave a number, not an address or a clue
But something in that photograph reminded me of you
Baby, let's put the X in sex
Love's like a muscle and you make me wanna flex
Baby, let's put the X in sex
Keep it undercover, baby, let me be your private eye
I got a call in the middle of the night
Heavy breathing never sounded quite so nice
She said, "Ohh, yeah, I wish that I was there"
I asked her who was calling but she wasn't playing fair

Sometimes you gotta suffer for the pleasure that you seek
You're begging for an eyeful but you only get a peek
Baby, let's put the X in sex
Love's like a muscle and you make me wanna flex
Baby, let's put the X in sex
Keep it undercover, baby, let me be your private eye
I heard somebody knocking, so I opened up the door
She wore a hat, shades and a trench coat
Wasn't wearing that much more
She said she knew my secrets but I didn't have a clue
Then I saw those black lace panties
And I knew that it was you
Baby, let's put the X in sex
Love's like a muscle and you make me wanna flex
Baby, let's put the X in sex
Keep it undercover, baby, let me be your private eye
Let's put the X in sex
Love's like a muscle and you make me wanna flex
Baby, let's put the X in sex
Keep it undercover, baby, let me be your private eye
Let's put the X in sex
Love's like a muscle and you make me wanna flex
Baby, let's put the X in sex
Keep it undercover, baby, let me be your private eye
Let's put the X in sex
Love's like a muscle and you make me wanna flex