We know that beauty is not just skin deep, but sometimes you just notice a scar or blemish on your favorite celebrity and wonder - what happened there?
Just like all of us, celebrities wear their war wounds from childhood accidents and serious injuries.
But you never can tell: sometimes the grisliest cuts come from a game of hide and seek, and the smallest come from a painful car crash.
1. Sharon Stone
The Basic Instinct star often hides her neck scar with makeup, or photo editing, or even a scarf.
But over the years it developed such a reputation that a website - www.sharonstonesscar.com - appeared to document its existence and explain its origin.
It turned out to be from a pretty serious injury. As a young girl, Stone was riding a horse when she ran into a clothesline, ripping her neck open.
While it's almost unnoticeable today, Stone is obviously self-conscious about the mark.
2. Padma Lakshmi
Watch as many Top Chef reruns as I have, and sooner or later you'll notice the seven-inch gash on host Padma Lakshmi's arm.
The actress and TV host has had the scar since she was involved in a serious car crash at age 14.
Her arm and hip were both shattered in the wreck, but Lakshmi has surprisingly pleasant memories of the accident.
"Being in a car crash was like an exhilarating hallucination," she told Vogue, "an unbelievable moment that oddly remains one of the most beautiful images in my memory."
3. Sylvester Stallone
Older readers will recognize the telltale marks on the Rocky star's temples right away.
They're often left behind when doctors use forceps to assist a baby's delivery - a technique that's barely used these days.
The scars actually give Stallone his distinct speaking voice and look, because doctors severed a nerve and paralyzed the lower left half of his face.
The small marks are just one entry in the action star's long list of injuries, which include a broken neck and a 70-stitch calf injury.
"I've had both shoulders done, my neck done, two back operations, Achilles tendon, and now this thing"”the peroneal tendon"”just ruptured," Stallone said about his body of work.
4. Kylie Jenner
When the reality star and supermodel posed with her boyfriend, Travis Scott, for the cover of GQ, her dramatic thigh scar captured a lot of attention.
The 20-year-old soon-to-be-billionaire has actually been very open about her famous blemish.
Jenner says she earned it during a dangerous game of hide and seek with her sister, Kendall.
"When I was about 5, my sister and I were playing hide-and-seek and I hid inside this really tall enclosed gate," she remembered.
"After a while when my sister didn't find me I had to climb up on this sharp pole sticking out from the gate. I slipped and the pole went into my leg. I tried pulling away to get the pole out but it just tore through my whole leg."
Ouch! As painful as it looks, the star told Celebuzz it used to be even worse.
"It's smaller now though because I grew!"
5. Jonah Hill
You may not have noticed it, but the Superbad star has a pretty nasty mark along his right elbow.
If you guessed that Hill's scars have a traumatizing, life-changing story behind them...you're right.
"This is one of the biggest things ever in my life," he said about the injury.
Hill explained he was just 15, and driving a borrowed car with his arm hanging out the window.
Hill's friend jerked the wheel as a joke, making the car flip over, dragging Hill's arm on the pavement.
The actor says he woke up in the hospital as doctors were discussing whether to amputate his arm, and the incident was a wake-up call for him.
"I said to myself, "˜I'll never let [my parents] down ever again,'" Hill remembered.
""˜I'm going to be successful. I'm going to resurrect what I put these people through by being a little ---.' So I look at this scar every day. That reminds me to work hard."
6. Harrison Ford
In Working Girl, Ford's character says he passed out while piercing his own ears and hit his chin on the sink.
In The Last Crusade, a young Indiana Jones cuts his chin with a whip.
But how did Harrison Ford actually get his famous chin scar? A car crash.
"A real mundane way of earning [my scar]," the actor said.
Ford was driving without his seat belt on in 1964, and struck his chin on the steering wheel after crashing into a telephone pole.
He was stuck by the side of the road for hours, until a good Samaritan drove him to the hospital.
Ford blames "inept emergency surgery" for why his scar is still so noticeable.
7. Seal
There are so many rumors about how this Nigerian-born singer got his facial scars that they sometimes meld together.
Was he attacked on the street? Were they part of a childhood ritual?
The truth is actually very plain, but still upsetting.
The "Kiss From a Rose" singer has a condition called discoid lupus. The skin condition causes inflammation, lesions, scars, and hair loss.
Many patients experience "butterfly" marks on the cheek and nose like Seal has.
Thankfully, he was treated for the condition in his early 20s, and it's been in remission ever since.
8. Michael K. Williams
He's played tough guys in The Wire, Boardwalk Empire, and Assassin's Creed, and his signature face scar always helps him fit the part.
The true story behind Williams' scar is pretty harrowing too. He was slashed with a razor during a bar fight on his 25th birthday.
Williams nearly died from his injuries, but the scars jump started his acting career.
They earned him roles as intimidating characters in music videos, which he flipped into a successful movie career.
9. Catherine Zeta Jones
It's small and subtle, but you've probably noticed the odd circular scar on Jones' neck.
It looks just like a tracheotomy scar - because in fact it is.
As a child, a virus stopped the actress from breathing, so doctors were forced to open her airway.
It can be easily repaired with surgery, but Jones says she's attached to the mark.
"Makeup artists are always trying to cover it up, but I don't want to hide it," she said. "I wouldn't be here today if I didn't have this scar."
10. Tina Fey
The Mean Girls and 30 Rock actress is famously private about her face scar, and she has good reason to be.
"It's impossible to talk about it without somehow seemingly exploiting it and glorifying it," she told Vanity Fair.
Fey was only five years old, and playing in her family's front yard, when a stranger slashed her face with a knife.
While the man who cut her was never caught, Fey says the injury didn't bother her until she started acting.
"I proceeded unaware of it. I was a very confident little kid. It's really almost like I'm kind of able to forget about it, until I was on-camera," she said.
Fey often uses makeup and camera angles to disguise the mark.
11. Kaley Cuoco
It's no surprise that the newly-married Big Bang Theory star will be sporting some marks on her shoulder, after getting emergency surgery this year.
But fans of the show might have noticed a serious scar just above her left ankle before.
Cuoco told Ellen DeGeneres the injury happened at horse riding lessons in 2010.
"It was the end of my lesson. I had been jumping all day. At the end of the lesson my horse spooked and I wasn't really expecting it and I fell off," she said.
"I was actually getting up but my horse was still kind of spooking. He was in the corner trying to get away from me. He leaped over me and landed on my leg."
Doctors had to insert steel bars in Cuoco's leg to rebuild it, but the sitcom star can laugh about it today.
"The good thing about that is I know when it's going to rain. I literally feel like I'm 110 years old "˜the storms are coming.'"
Did any of these stories surprise you?
Here are more interesting celebrity stories: