The film begins with a mystifying shot (lasting four minutes) that starts at the title of the film and brings us through the Hot Traxx nightclub. In these first four minutes Anderson establishes the setting as 1977 San Fernando Valley (the world capital of porn), and introduces us to no less than nine characters. The shot ends on a medium of the main character: 17-year-old Eddie Adams. Very quickly we learn that Eddie lives way out in Torrance, causing a long commute just to bus tables at this particular club. Because of its significance (Eddie's yearn to enter the porn hip Hot Traxx scene), I consider this to be what Truby calls the Ghost. He's already gotten the job that puts him in the eyes of Porn Director Jack Horner, who identified Eddie as potential immediately. A possible secondary Ghost could be the simple fact that Jack Horner has been making "exotic pictures" for years now, and he's about to produce another one in a few days.
Through dialogue with his girlfriend Sheryl Lynn (scene 18), we discover that he aspires to greatness of some sort or another. He expresses that "Everyone is given one special thing", being in this case his enormous penis. This establishes his Want as becoming a successful porn actor. It is through Eddie's exchanges with his Mother (scenes 13 and 25), where she berates him, abuses him, and derides him furiously that we discern his Need as both proving himself as a person with some redeemable traits as well as finding a loving and caring environment that he didn't find with his own family.
Ostracized from his home, he finds solace in friend and Ally Jack Horner. Jack takes him in, introduces him to the crowd, and makes him feel at home. He also gives him a scene in the upcoming film he's producing. It's after an incredibly efficient party scene (that includes an awesome six and a half minute steadi-cam shot that follows each of the nine characters previously established, goes underwater, comes back up, then goes back down), that Eddie creates his alter-ego: Dirk Diggler.
(From Scene 50)
When I close my eyes . . . I see this thing,
a sign . . . I see this name in bright blue neon
lights with a purple outline. And this name
is so bright and so sharp that the sign --
it just blows up because the name is so powerful . . . .
A BRIGHT NEON SIGN IN BLUE LETTERING, WITH A PURPLE OUTLINE:
It says, "Dirk Diggler."
The NEON SIGN FLASHES, BUZZES, THEN BURSTS INTO AN ELECTRIC FLAME.
The moniker of Dirk Diggler proves to be Eddie's vehicle of ascension to Adult stardom but also proves to be his vital character flaw. Eddie/Dirk's first scene, a porn-done-audition between Dirk and Starlet Amber Waves introduces him to the world and establishes him as something special. This is most definitely the Inciting Incident or catalyst that propels Diggler into the world of adult film. This helps him to achieve his Desire, which is to become a star. This achievement is evident both in scene 60, where we read praise of both Dirk and Jack's success with Diggler's first film Spanish Pantalones and in scene 75 where Dirk wins three Adult Film Awards.
At this point we see Diggler enjoy his success for two years, building up both his bankroll and his ego. Dirk Diggler becomes bigger than Eddie Adams ever anticipated, getting lost in new houses, corvettes, and more awards. His rise culminates in scene 87: the New Years Eve party. It is here that Amber Waves introduces Dirk to cocaine, starting him on a mudslide to failure, poverty, rejection, and paranoia. At this point the film itself takes a turn in direction from positive to negative, up to down. Dirk's demons grow with his addiction as he grows closer to bad boy Todd Parker (conveniently introduced at the party with the sound of a car crash as he slams through the gate). A new face appears on the scene; a young kid named Johnny Doe. Dirk sees Jack giving Doe the same spiel he received when he was just starting out and feels threatened by this new blood. Fitting into the Truby mold, I'd call the Opponent in this sense both Johnny Doe and Dirk Diggler, since he causes his own downfall.
The drugs alongside Dirk's growing hatred for Doe eventually come to a head in scene 117 where he has a problem preparing for a scene (i.e. becoming erect) and gets in an argument with Jack. This leads to his banishment from The Horner household and onto his own. Now, consoled by new friend Todd Parker and loyal compatriot Reed Rothchild, Dirk embarks on his new Plan for stardom: Music. In what can only be described as hilarity, coked out Dirk Diggler and Reed Rothchild try to put some magic down on audio tape only to spend all their money on drugs and time in the recording studio.
Finally, in solemn scene 165, a surfer looking for male companionship picks up Dirk. After a few minutes the surfer's friends arrive and beat him up, calling him a homosexual as they kick and punch. This is the very epitome of Apparent Defeat.
There is one final Title card before scene 170 stating "Long Way Down (One Last Thing)" which eschews the third act of the film. At this point Dirk has just hit rock bottom. He's destitute, he's addicted, and he's scared. Todd parker comes up with a Plan that involves passing baking soda off as cocaine in order to score some extra cash. We follow the group to Rahad Jackson's house, a rich entrepreneur who has a penchant for smoking crack and keeps a Chinese guy who really likes firecrackers around for kicks. It's during this scene (173) that I believe Dirk makes his self-revelation. As the deal is going down, the camera stays on Dirk as he stares blankly into space for thirty seconds. Suddenly he snaps out f it, realizing where he is and wondering how he got there. Nothing is said but Mark Wahlberg plays the part so well that I believe he's realizing everything. At that point, with so much going on and the tension in the air, Dirk wakes up. At this point he's ready to leave.
Unfortunately, Todd Parker has a different agenda, and a Battle ensues. Dirk is forced to run for his life, experiencing a brush with death as his window is shattered just as he's getting in his car. By the time he comes down from it all, he finds himself on Jack Horner's doorstep. He enters, asks Jack for help, and returns to a New Equilibrium.
Morally speaking, I believe Dirk to be at a higher position once returned back to the Horner family. He's matured to a point where he realizes what he has and doesn't take it for granted. He's fulfilled his need in becoming an accepted part of Horner's pseudo-family and having something to be proud of (besides his enormous member).
It should be noted that the final cut of the film omits several scenes in the shooting script (most of which are featured on the DVD). Of all the cuts made however, only one real subplot was omitted from the final cut. Most of the scenes that didn't make it were just small exchanges that establish mood or character. The majority of these scenes were cut because they simply weren't needed (the DVD also contains director's commentary on each of the deleted scenes, explaining where the scene fit and why it was cut). Since the film as it is runs over two hours, a lot of extra fat needed to be cut, so director P.T. Anderson made a decision to cut a fairly major sequence involving two minor characters because of flow and time.
Perhaps the largest difference between the script and the final cut is the end. In the script, we stay with Rahad Jackson after he chases Dirk, Todd, and Reed from his house with a shotgun. Sirens can be heard and Rahad goes completely insane, hauling out an arsenal and preparing for battle. In the final cut we cut from Rahad to follow Dirk to Jack's house. However, in the script, Dirk doesn't go directly to Jack's house. He goes back to his parents' house and finds his ex-girlfriend Sheryl Lynn, who's moved into the house. She explains that his parents died a few months ago in a car accident (that happened to involve a drunk kid named Johnny Doe) and she moved in with her husband after that. She then tells Dirk that she knew he'd "do something special," acknowledging his accomplished Want.
This alternate ending is not on the DVD, but Anderson speaks of it in his feature-length commentary, stating that, after thinking about it, he didn't really like how every character was neatly tied up and explained. So he cut it, both for time and content. Although I'd like to see the footage, I'd have to agree with his decision.