Full disclosure, right up top.
* All the dunks in this film are real. No basketballs, backboards or rims were harmed in the making of this video, but we cannot speak to the egos of the hapless defenders who have been posterized by USC's Marcus Johnson.
** While this video is 41 seconds long, it does not include some of Marcus Johnson's best dunks, which occurred before everyone realized a camera should follow him every time he steps on a basketball court.
The first time it just happened.
One day he was a skinny seventh-grader closing in on 6 feet and grabbing the rim several times a day. The next he was throwing down one-handed windmill dunks wherever he could find a basketball and a hoop.
"I mean After the first time I did it, I just knew how. It's like your body just gets the form, just kind of memorizes how to do it,'' he said with a little shrug.
He's a little shy about it at first, as if he thinks everyone can dunk the way he can.
But Marcus Johnson knows.
You can see it in the dunk last year against California, when he seemed to use Golden Bears forward Jorge Gutierrez as a stepladder on his way to the rim he knows.
You can see it in the alley-oop from teammate Mike Gerrity against Washington a few weeks ago, when Gerrity launched a pass from behind half court to somewhere in Johnson's vicinity, knowing the 6-foot-6 swingman can catch and dunk just about anything.
Marcus Johnson knows, because how could he not?
He hears the way the crowd doesn't just roar after one of his dunks, but gasps and screams and immediately checks the replay screen above midcourt just to make sure he really did jump that high and he really did just dunk like that.
"I mean, my adrenaline is rushing, too,'' he admits. "You just got the dunk, then you hear the crowd,\; everything's flowing. It just brings a smile to my face.''
How about looking up at the screen for the replay?
"Nah, you gotta get back on defense,'' he said softly. "You don't have time to look up and find the screen. You gotta get back on defense.
"But I'm not going to lie, if someone tells me afterwards that it looked nice, I'll go back and watch it later.''
The thing is, as we advised earlier, most of his best dunks aren't on video.
They happened in practice or in a high school gym or some outdoor court no one has ever heard of, on a metal rim that rattles like a nickel slot machine paying out a jackpot.
Only those present really know what happened and how high he flew, which leaves a lot of room to color outside the lines in the retelling.
In an odd twist, Johnson said his best dunk didn't actually go through the rim.
"I still say the highest I've ever jumped was against [Compton] Dominguez High,'' he said about the memory of his days at Westchester High and those great rivalry games.
“
I jumped from, like, the free throw line, and when I got to the rim I was still so high I kind of scared myself and I missed the dunk. That's the highest I've ever jumped in my life.”
-- USC swingman Marcus Johnson
"I jumped from, like, the free throw line, and when I got to the rim I was still so high I kind of scared myself and I missed the dunk. That's the highest I've ever jumped in my life.''
His other favorites:
"I like the Gutierrez dunk,'' he said. "And a few back in AAU where I windmilled on these guys. Or maybe this alley-oop from [center] Hilton Armstrong [a former teammate at Connecticut]."
"My first dunk, that was special too. I was in the seventh grade. Now I totally remember. We were at Del Aire Park in Hawthorne. It was spring break. I remember because my AAU team was about to go to Vegas. I was like 5-10, 5-11. And I'd been grabbing the rim all the time, like six or eight times a day.
"Then one time I just did it. One-handed, since I've been able to palm the ball since I was young. And everyone on the court just looked up and got excited. I did too. I think I surprised myself. I just started running around the court all excited.
"After that, I just fell in love with dunking. It's all I wanted to do.''
Still think he's shy? Yeah, not so much.
The thing is, when you're as good at something as Johnson is at dunking, it's easy to get pigeonholed.
It's all anyone ever wants to ask you about or see you do. Which is fine when you're 15 and the best athlete in every gym you walk into. But not so great when you're 22 working your tail off to become a more complete player and trying to get NBA scouts to realize you've got the defensive chops to make a six-figure paycheck in the league.
"They're not going to come and get him for the way his dribbles, his scoring ability or his dunking,'' said USC coach Kevin O'Neill, who coached in the NBA for seven years.
"For Marcus to make it in the NBA, he has to get a reputation as a lockdown defender, [an] athletic guy that can guard multiple positions. Which I think he can do.''
Johnson is averaging 10.0 points and 4.7 rebounds in his senior season for the Trojans. While he's not the team's leading scorer, he's probably USC's most invaluable player.
"He's become the guy that as his energy goes, so goes our team,'' O'Neill said. "He's been a huge impact for us this year; without him we'd really be screwed.''
What O'Neill is still trying to understand is how such a talented athlete flew under the radar for his first two seasons at UConn and then last year at USC.
Johnson had been highly recruited out of Westchester High in 2005, even earning mention as a possible one-and-done candidate.
For some reason, though, it never came together on the court, and Johnson transferred to USC after playing in one exhibition game during his third year at UConn.
"There were a lot of issues,'' Johnson said. "I had some family issues back here. Me and coach [Jim] Calhoun just came to an agreement that maybe it'd just be best for me to come home.''
When Johnson arrived on USC's campus, his favorite jersey number, No. 1, wasn't available. Symbolically, No. 0 seemed like a fitting choice.
"It's just a fresh start,'' he said. "My No. 1 was taken, so I just felt like I should start from scratch. I'm not trying to be the whole zero-to-hero guy it's just a new beginning for me.''
All in all, a quiet launch. Or at least that's how he intended things to go. Then he started dunking.
"Sometimes,'' teammate Alex Stepheson said, "man, I don't even know what to say. He's just incredible. You throw it 10 feet around the rim and he'll jump and go get it.
"I'm always on the court going, 'Dang, did he really just ? And he took off from where ?' He's just incredible.''
Ramona Shelburne is a writer and columnist for ESPNLosAngeles.com.