Lance Bass says he's come to peace over his late former manager, Lou Pearlman, and it sounds like a new documentary about the guy helped with that process.

We got the former 'NSYNC singer at LAX Friday, where our photog asked about a new doc coming out that covers Lou's sheisty dealings and financial crimes while he managed Lance and co., as well as the Backstreet Boys in their heyday. It's called 'The Boy Band Con.'

If you aren't familiar, Lou got sent to prison in 2008 for running one of the largest Ponzi schemes ever. He pled guilty to conspiracy, money laundering and other financial crimes ... and got sentenced to 25 years in prison. He died behind bars in 2016.

More relevant to Lance ... Lou stands accused of robbing his artists blind throughout his career by way of shady business practices -- aka fraud. 'NSYNC, The Backstreet Boys and even Aaron Carter all sued Lou in federal court ... and either won or settled.

Brian Littrell's reaction to Joey Fatone suggesting the Backstreet Boys and 'NSYNC come together in one super boy band is pretty simple -- Bye, Bye, Bye ... it ain't happening until you get Justin Timberlake.

We got the BSB singer Thursday at LAX, and he absolutely destroyed Joey's dreams of the pop pairing that, honestly, would be Larger Than Life. Brian's point is ... right now BSB is bringing a lot more to the table than 'NSYNC can.

He's got a point. Backstreet was Grammy-nominated this year, starred in a Super Bowl commercial with Chance the Rapper ... AND they have a Vegas residency. All of that equals relevance.

But watch, Brian does offer a small ray of hope.

If Joey really Wants it That Way, all he's gotta do is get JT on the horn ... and then wait another 10 years or so. LOL!!!

When you're about to get one of the richest contracts in sports history ... what do you get your wife for her birthday?

Bryce Harper got his wife THE BACKSTREET BOYS!!

The MLB superstar took his wife to see the guys at Planet Hollywood in Vegas over the weekend -- and not only got her backstage for a meet and greet ... but, had the guys take her on stage for a 5-on-1 serenade!

Check out the video as Kayla Harper gets a flower and a special rendition of "Shape of My Heart" from AJ, Howie, Nick, Kevin and Brian!

After the show, Kayla wrote, "My 9 year old self lost her mind last night. Bryce has been surprising me with little gifts all week and one of them happened to be a black dress that he said I needed for Sat night."

"He let me know at dinner that he was taking me to see the Backstreet Boys... little did I know, the biggest surprise of them all was meeting them & then having them pull me onstage to be serenaded."

AJ McLean has all but signed up to be Demi Lovato's sponsor when she finishes up with rehab ... and he's got an entire plan laid out for her if she's listening.

We got the Backstreet Boy leaving Craig's in WeHo Tuesday night and wanted to know if he has some advice for Demi on how she can stay on the right path once she's out of rehab. Remember, AJ's been open about his addiction in the past and he's been on the straight and narrow path ever since.

AJ personally offers to help Demi battle with addiction and seems to have a plan that's relapse-proof. Among the advice -- surround herself "with people that aren't gonna 'yes' you to death." It's been just over 2 months since Demi's near-fatal overdose, but she seems to be doing much better these days.

AJ McLean says Mac Miller's death was premature and tragic -- and he hopes more deaths can be prevented with a potentially life-saving measure he'll be rolling out soon.

We got the Backstreet Boys member in Bev Hills where he was participating in the Ante Up! for a Cancer Free Generation poker tournament -- which raises money for cancer research -- and he gave us his thoughts on Mac dying Friday from an apparent overdose.

While he's never met Mac himself, it's clear AJ's shaken up over his passing -- explaining people need to realize how big an issue drug addiction really is ... and how to overcome it.

He then tells us about a new detox kit he's working on that he says will help people kick drugs safely ... particularly, opioids. AJ says his kit includes non-narcotic medication -- unlike other drugs often used in opioid treatment, like methadone -- that won't get 'em hooked.

AJ McClean will never forget the night the Backstreet Boys got to share the stage with Aretha Franklin ... as her backup singers.

We got AJ Wednesday at Malibu Country Mart, and he couldn't stop singing his R-E-S-P-E-C-T for the Queen of Soul. He shared an awesome story from Backstreet's 2001 performance with Aretha and Stevie Wonder.

Just wait until you hear AJ recall his adventure getting Stevie through an obstacle course and out onstage!!!

AJ says he grew up listening to Aretha, and she had a profound influence on the Backstreet Boys and ALL genres of music. AJ was a huge fan of "The Blues Brothers" and loved Aretha's cameo in it.

He hints at possible tributes to Aretha at future Backstreet Boys' performances ... and also shares his thoughts on the perfect songs for the star-studded lineup performing Friday at Aretha's funeral.

As we reported, Stevie, Ariana Grande, Chaka Khan, Jennifer Hudson and many others will be onstage for the service, and you can see the whole thing here -- TMZ will be streaming it live.

The 14 or so people injured by a tent collapse before a Backstreet Boys concert this weekend are lucky to be alive based on this woman's first-hand account of the accident ... which sounds terrifying.

We spoke with Oklahoma resident Rhonda Dunn, who was one of the at least 14 victims injured at the WinStar World Casino and Resort Saturday after an awning fell on people waiting in line. She recounts the moment the tent collapsed ... fighting back tears to do so.

According to Rhonda, she was pinned under the structure before some heroic bystanders helped lift enough of it for her to get out. She didn't walk away unscathed though -- Rhonda tells us a doctor told her she'd suffered a compression fracture on her spine.

Tom Brady can cross sixth member of the Backstreet Boys off his post-football plans ... 'cause AJ McLean says the Pats QB's singing is way too garbage for that.

We brought you the story last week ... TB12 had a date night with Gisele out at U2's concert in Boston when he screeched out the words to "Vertigo" and "Pride (In The Name of Love)."

When we showed AJ the clips ... his reaction was the same as mostly everyone else's ... "Not everybody is supposed to be a singer."

McLean did give props to Brady for sharing his, um, voice with the world ... saying it took "cajones" for Brady to do that.

The boy band basketball turf war just got REAL -- with Brian Littrell telling Joey Fatone that Backstreet will straight DOMINATE 'NSYNC on the hardwood.

And get this -- Brian says it'll only take 2 of the Boys to hoop up 'NSYNC's entire roster!

"They’ll lose, plain and simple," Littrell told TMZ Sports at LAX. "You can take myself and Nick against all 5 of those dudes and we’ll be cool."

Brian ain't playing -- telling us he's got a court at home to keep his game tight.

So, if Joey, JT and co. really want it like Fatone said, Littrell's down ... and says he wants 10 racks on it!!

"When we win, I’ll donate my $10,000 that I have on the game to charity. Joey can pick it."

The boy band era is over, but the smack talk remains -- because Joey Fatone is telling the world if his crew ever had to face the Backstreet Boys in hoops, they'd make them go "Bye Bye Bye."

We got Fatone out in Beverly Hills and showed him footage of his ex-bandmate Justin Timberlake draining half-court shots, and asked him if JT really has the goods on the court.

Fatone said yes, but things got really spicy when we asked whether or not the rest of 'NSYNC could ball. More specifically, if they could take out the Backstreet Boys in hoop-life warfare.

"There's no think so. You tell that to Nick Carter."

Challenge issued.

BTW, we found some footage of the two crews playing back in the day. It ain't exactly Lakers versus Celtics ...

The Backstreet Boys are ready to drop the mic ... in the restaurant biz!!!

BSB Entertainment Inc. -- a company with A.J. McLean, Howie D., Brian Littrell and Nick Carter listed as directors -- filed docs, which were obtained by TMZ, on February 9 to trademark "Backstreet Barbecue" for use in a new restaurant.

The news comes on the heels of Nick telling a food blog they're looking for a partner in Mexico to start making their own tequila. Hey, it worked for George Clooney. Now add a BBQ joint and the boys have quite the trifecta (music reigns, of course).

AJ McLean isn't even trying to hide it ... he's totally looking forward to getting his very first prostate exam, now that he's hit the big 4-OHHHH!

We got the Backstreet Boys singer Tuesday -- the day he actually crossed over -- and asked if he'd scheduled his first, y'know ... oil check, now that he's a man of a certain age.

AJ knows he needs to get it done -- probably sooner than later, it sounds like -- but the good news is he's excited about who's conducting the examination. He also reassured us his wife's on-board with another woman getting up in his business.

Former Dream singer Melissa Schuman claims Nick Carter raped her back in 2002 ... when she was 18 and he was 22.

Melissa says she and the Backstreet Boys singer started talking because their managers suggested they date -- presumably for good PR -- even though she says she already had a boyfriend.

She claims Carter invited her and a friend to his Santa Monica apartment for what she calls a "casual hangout" -- and after some boozing he started making out with her. In a very graphic blog post, Melissa claims he eventually took her into a bathroom, he forcibly performed oral sex on her ... and then forced her to reciprocate.

Melissa says she repeatedly told him she did not want to have sex, and was saving her virginity for her husband. She claims Carter took her to a bedroom, and then forced her to have intercourse.

Schuman says she told her manager about the alleged rape, but was told Carter's legal team was too powerful, and publicly accusing him would hurt her career.

Houston Astros superstar Jose Altuve LOVES the Backstreet Boys -- and it turns out, the feeling is mutual.

A.J. McLean says he saw the rendition of "I Want It That Way" that Jose and his Astros teammates shot in the team locker room last year ... and now he wants to collaborate!

The Backstreet Boys singer admits Altuve ain't exactly the songbird of his generation ... but his voice is good enough -- so he extended the slugger an invite to sing with the band.

Please say 'yes.' Please. Please.

If A.J. McLean and Joey Fatone can wave the boy band white flag and come together onstage ... then maybe there's hope for America too.

The awesome duet went down Saturday night during Joey's 40th birthday bash at Ora nightclub in Miami. The former pop rivals decided to serenade the crowd with the Backstreet Boys hit, "I Want It That Way."

You'd think they'd do an 'NSYNC tune ... it was Joey's night after all, but the crowd ate it up, anyway.