The film begins with young Nikki Sixx, previously known as Frank Carlton Serfino Feranna. We see Frank in his childhood household with his mother, and his abusive stepfather. 

Frank and his mother get into an argument, which causes him to act impulsively, and cut into his arm with his pocket knife. The police later showed up to Frank’s house to question him about the incident. Frank framed his mother for the cut, and said she was the one who inflicted the injury on him. Frank’s mother begged him to tell the truth to the police, but Frank wouldn’t budge.

After the situation with Frank and his mother, Frank was no longer under her custody. Frank was living day-to-day on his own in his teen years, and actually tried to reach out to his birth father during this time. Frank Ferrano, Frank’s father, received a call from Frank in his late teen years from a payphone, in hopes to build a bond with him. Frank’s father shut this down immediately, and Frank realized he doesn’t not want to share a name with a man who wanted to do nothing with him. This pushed Frank to go to the courthouse and legally change his name. This is when Nikki Sixx was born. 

Nikki went on to begin preforming with various musicians in Los Angelos. This is when we are introduced to the vibrant character of Tommy Lee. Tommy Lee has been hearing rumbles about Nikki Sixx and his “charming” personality and was eager to get a hold of him. Tommy is found having a dinner date with his girlfriend after a show they attended, when he spotted Nikki Sixx seated at a table across the room.

Tommy had been playing for a band called Suite 19, while Nikki had been playing for London, so Nikki was briefly familiar with Tommy. Tommy approached Nikki in a nervous manor, and sat down for a chat with him. Nikki entrained Tommy but was ultimately uninterested, until Nikki noticed Tommy’s impressive drum stick spinning.

Nikki and Tommy decided to team up in hopes of creating their own band. We are now introduced to Tommy, Nikki, and a guitarist who is auditioning for a spot in their band in their small apartment. Nikki had posted an ad in the local newspaper for auditions for the group, and this guitarist showed up to try to get a permanent place. While they are practicing, a car rolls up to the apartment with an older gentleman in it. Tommy and Nikki take a break from practicing with the potential guitarist to greet the man outside. This is when we meet Mick Mars. Mick was also looking to audition for the band, and had much experience playing. Tommy and Nikki picked on Mick for being older than the two, but Mick seriously impressed them when he went upstairs to start playing. The other guitarist wasn’t blending well with the group so Mick turned to the guitarist and told him to get lost.

Now the band was starting to get into a good flow. Nikki was shredding on the bass, Tommy was whipping out insane tricks on the drums, and Mick had been a season guitarist for years now. However, they were missing an important piece: a lead singer.

The boys followed Tommy to a concert that was being held at a pool party in hope to snag their singer. Vince Neil had a “beachy” vibe to him. Long, blonde, curly hair, a surfer boy outfit, and girls drooling over him. Nikki and Mick were hesitant of Tommy’s suggestion because they could tell their aesthetic was very out of place in a scene like this. However, Tommy knew what he wanted. Tommy approached Vince after he was finished singing, and it was revealed to the audience that Tommy and Vince had been friends back in high school. Vince even stayed with Tommy’s family while he was struggling with his home life.

Tommy told Vince he should come try playing with the band sometime to see if it would be a good fit for him, and Vince was happy to take up on the offer.

We now are brought back to the apartment with Nikki, Tommy, Mick, and Vince to have their first test run together. Vince also brought alongside his girlfriend to listen to their music. The boys begun to play, and something just felt off. Vince’s girlfriend called them off, and explained to Vince how she thought this was too heavy of music for him. Nikki made some suggestion about how they could switch up their tempo, and speed to make things flow better. The boys took a second shot at the song with these slight modification, and Vince’s girlfriend’s jaw dropped. This is when they knew legends were about to be born.

It’s about time for the band to begin showing their music to the world, but before they can do that, they needed a name. They needed something catchy. The guys are hanging around the apartment trying to brainstorm ideas. Nikki came up with a name, but the group feels it’s to dark, and a bad play on words. They gave Tommy a shot, but rather than taking it seriously, he turned it into a joke and delivers poor names as well. Finally, Mick snatched the notebook and wrote something down. He flashes the notebook to the other band members, and slow smirks begin to rise on their faces. The notebook read, “Motley Crue.”

Now that they had their name, it was time for them to shine under the stage lights. However, when they arrived to their venue, it was some what of a crummy turn out. The audience was sparse, but the boys were still ready to give them a show. They came out blazing with a make-shift set, and list of sings written in sharpie by Nikki, and bizarre costumes and makeup. Vince announced the band to the crowd and just as there were about to begin the show, Tommy’s drum-set falls apart.

Snickers begin to starts from the crowd, and a man starts to heckle the band. The members of Motley Crue take immediate offense to the hecklers harsh comments, and they pounce on him. Fight breaks out between all members of Motley Crue, and people in the crowd. Eventually after the band was done kicking some butt and the crowd goes silent, a man in the crowd starts to cheer for Motley Crue. Others in the crowd caught along. Their performance that was looking like it was about to be the biggest flop in history, had actually turn into a success after the crazy episode.

Word got out about Motley Crue’s crazy actions, and more fans started flooding into concerts. They went from just a few people, to completely selling out these small venues. People couldn’t get enough of the outrageous Motley Crue. This is when we meet producer Tom Zataut of Elekra Records, who offers them a five-year signing deal with the company. The band agrees.

Because of the huge shows they began selling out, the money started pouring in. Money was not good for Motley Crue. The blew it on big parties, expensive items, and a plethora of drugs.

Motley Crue is a big dog now, and they are invited on their first tour, along side hit singer Ozzy Osbourne. While they are on their tour, the band decided to hang out by the pool during some down time. However, the band, and all the other pool-goer’s were interrupted by Ozzy’s intense appearance. Ozzy sits down with the boys and explain how they need to be careful when on tour. He preaches about being safe and smart, while ironically snorting ants off the ground, and licking his and Nikki’s urine off the pool deck.

The group doesn’t take Ozzy’s advice well and we see tons of clips of the boys being menaces to those around them. The boys are seen through things out of windows, smashing everything in their sight, banging on peoples doors, preforming public nudity, and doing lots of cocaine. Vince meets his future wife Sharise, who he falls madly in love with. On the other spectrum, Tommy getting into a brawl with his girlfriend on the tour bus in defense of harsh words she was throwing at his mother, and the two eventually split.

On December 8, 1984, Vince throws a house party at his place in Redondo Beach. Here, Tommy catches a glimpse of one of the ladies who works on MTV and decided to take a chance and go up to her. They hit it off and Tommy notes that he’s already in love with her after a few minutes. 

However, love at first sight wasn’t the only monumental thing that happened this night. We meet Razzle, a friend of the boys, who played for Hanoi Rocks. Razzle was alongside the boys for a while at this point in the film, and he was in attendance at the party. Razzle and Vince decided they needed to go on a “booze run” to pick up more liquor for the party. Both en were heavily intoxicated before Vince decided to get behind the wheel, and Razzle hoping into the passanger scene.

We then see the two men driving on the road while having a goofy conversation with each other You can notice how invested Vince is in the conversation because he keeps his focus more on Razzle than on the road. Eventually, Vince begins drifting into the oncoming lane, and crashes with two other cars before coming to a holt. Vince awakes to Razzle’s head laying in his lap, fire surrounding the scene, blood, and a busted up car. Razzle was dead. Vince was sentenced to 30 days in jail, but actually spent only 19.

We now fast forward to a live without Vince. The boys are falling more into the scene of sex, drugs, and crime more than they ever were. Nikki in specific is becoming increasingly addicted to herion. Nikki is constantly shooting up, and we really see how extreme it had gotten on Tommy’s wedding day. Nikki was Tommy’s best man, but was proving himself untrustworthy with his sloppy behavior. He was cloudy, falling over things, and slurring his speech. Mick Mars offered to stand in his place for Tommy’s sake.

Nikki is in a very dark place now. We catch him in a gloomy room with other addict, many of whom or passed out on the couch. There is a small easter-egg hidden in this scene when we same a man with long curly hair passed out on the couch. This is an addition at Steven Alder, a member of band Guns ‘N’ Rose, who was actually present at the time of Nikki’s overdose. Nikki was so weak at this point that he actually had a fellow addict inject into his veins because he wasn’t strong enough to.

Just like that, Nikki went down.

Nikki was officially declared dead, but the paramedic working on him was such a huge fan that he would not let Nikki die in his hands. He gives him two shots of adrenaline, and Nikki is brought back to life. Nikki realizes he has hit rock bottom, and swear to never use again, but he wakes up the next morning with a needle in his arm. This is when he quote, “Now this is rock bottom.”

It was time for Motley Crue to make a change. Nikki decides its time to take the band to rehab. Motley Crue emerges in 1989 as a sober band with their album Dr.Feelgood, which becomes their first number one album on Billboard 200. They follow the release of this album with a lengthy world tour, but the sobriety begins to get to lead singer Vince, and drummer Tommy, and the pick up the bottle again. Vince became annoyed with practices and bickering with his band mates, and was struggling to be away from his family. Tommy on the other hand, was looking for comfort in other women while on the tour, and was exposed in a magazine that eventually lead to his divorce with Heather.

Vince is greeted by the rude awakening that his wife Sharise and daughter Skylar packed up and left him while he was on tour, due to missing so much time with them. This triggered Vince to fall into a depressive episode and leave the band. The band hires John Corbai as his replacement, but fans want to see Vince singing with the group, not John.

If there wasn’t enough for Vince to juggle, his daughter Skylar fell ill with stomach cancer. We see him by her side for much of it, but ultimately there was nothing he could do to save her. Skylar dies of stomach cancer at the age of four.

Nikki starts to realizes how the uproar of John coming iin as their new lead is effecting the band, and decided to meet with their producer Tom on final time. Nikki requests for the rights to their music back, and Tom is more than willing to give them. Tom explains how they have been reaking havoic for him for years, but they had some sweet memories that he will cherish forever.

Now that the rights to their music was theirs again, Nikki needed to get the band back together. He started by visiting Tommy, and after a few snarky remarks from Tommy, they were back to pals like nothing ever went dow. Nikki apologized for the stunts he pulled at his wedding, and the two were off to gather Mick.

Tommy and Nikki picked Mick up from the hospital after his hip replacement surgery due to his chronic arthritis. They poked fun at him for being an old man, but Mick knew they had come for the right reasons: the band was getting back together. There was one last stop they had to make.

Vince is hanging out at the bar, having a beer and watching some television, when the three boys stroll in. Vince agrees to talk to the other members and they all sit down and dissect their actions. They finally reconcile, and decide to give it another shot.

Motley Crue went on to play for 20 more years.