Tommy decides to act on his plan to kill Diaz. He meets up with Lance on the bridge to Starfish Island, and Lance provides Tommy with an M4 Carbine. They enter Diaz's Mansion and manage to shoot their way through the mansions gardens. They enter the mansion through the back door, next to an indoor pool, and shoot their way through the hallways. They eventually reach the main hall where Diaz is waiting, having spotted them entering his property through CCTV.
Diaz has eight guards as protection but they, along with Diaz himself, are killed. Diaz manages to crawl to the top of the stairs, claiming to have trusted Tommy, before Tommy and Lance kill him.
On the iPad version, a glitch may occur causing Lance to shoot Diaz during the cutscene where Diaz exits his office.
If the player infiltrates the mansion via the roof, they will not encounter any guards until they reach the hall.
The reward for completing this mission is $50,000 and the missions Love Juice and Shakedown are unlocked. Three of the Chopper Checkpoint missions have been unlocked too, as well as more weapons at the Downtown Ammu-Nation. The player can now save their game at Diaz's mansion (now renamed the Vercetti Estate) and store vehicles in the mansion's garage. It is also now possible to gain a six-star wanted level.
Tommy and Lance enter the mansion from the basement and head upstairs, killing more of Diaz' goons along the way, until they reach the main room, at which point, Diaz comes out of his office and decides to face off against Tommy and Lance.
Kent Paul: Tommy son, have I got a surprise for you, I'm down at the recording studios with some major artists. Why don't you pay us a visit? You know it makes sense, dontcha? See ya later.
Phone Call 2
Sonny Forelli: Tommy, remember me?
Tommy Vercetti: Hello, Sonny.
Sonny Forelli: That's right, Sonny. We're old friends. You never write me, you never call. Don't you want to be friends no more?
Tommy Vercetti: I've been busy trying to sort things out. You didn't give me a lot of support down here, Sonny.
Sonny Forelli: Oh, my fault is it? Well, I've heard you been busy all right. Busy killing drug barons. Busy taking over. Don't forget about us, Tommy. 'cause I can assure you, I ain't forgetting about you.
Tommy tells Lance to look out for Diaz's bodyguards that will be sprawled out in the territory.
Tommy and Lance killing the guards at the front door.
Tommy tries to enter the mansion through the front door, however the door appears to be locked.
Tommy and Lance fighting their way through the estate.
Tommy and Lance taking out the guards in the basement area at the back of the mansion.
After some time, Tommy and Lance come across an entrance at the back of the mansion, near the pool area that supposedly leads into the mansion's basement.
Tommy and Lance heading inside.
Tommy and Lance taking out the guards on the main staircase.
Tommy and Lance taking out Diaz's bodyguards in the main room of the mansion.
After taking out all of the bodyguards, Tommy calls out for Diaz, who comes out of his office, armed with the MP5.
Diaz is angry at Tommy for betraying him and saying that Tommy's betrayal will be repaid with death.
Tommy shooting Diaz down.
Diaz is defeated and crawling on all four.
Diaz is yelling at Lance and Tommy for destroying his luxury mansion.
Lance tells Diaz that this is for his brother's death at the hands of Diaz, and kicks him over.
Diaz pleads with Tommy and tells him that he trusted him.
Diaz tells Tommy that he would have had him made, not realising that Tommy is already a made-man in the Italian mafia.
Tommy and Lance ignore Diaz's pleads and point the barrels of their guns at him, wishing him goodnight, before shooting him in the face.
Several hours pass after Diaz's death, and Tommy has now taken over his protection racket and his mansion now belongs to Tommy.
GTA Vice City - Walkthrough - Mission 20 - Rub Out (HD)
GTA Vice City - iPad Walkthrough - Mission 20 - Rub Out
This is one of two missions (the other being The Job) to have a reward payout higher than the final mission.
The mission is very similar to a scene in the cult classic film Scarface, which had a drug lord (Frank Lopez), who is similar to Diaz, gunned down by his former comrades after betraying them (Tony Montana, the protagonist and Manny Ribera, a close friend of Tony) in his headquarters, as his former comrades take over his crippled empire after his death.
The shot of Lance opening the trunk and him and Tommy preparing for a raid while the camera is in the trunk of the car resembles a scene from the classic 1994 crime film, Pulp Fiction. 
Following this mission, the Diaz gang will only be encountered in Rampages (in which case they will be hostile to Tommy), as well as in Firefighter and Vigilante missions.
This is one of the few missions that feature the Desert Eagle (Lance holds it in the final cutscene), despite being unavailable for use in the game.
Originally, Lance was supposed to talk to Tommy about taking over Diaz's empire after the two kill him. This speech is unused in the game, however, it still remains in the game files, as it is a part of the same audio file as the audio for the cutscene where Diaz gets killed.
↑A shot from Pulp Fiction that may have inspired a similar shot in the intro cutscene where the two characters equip guns from their car trunks and prepare for a raid, while the camera stays in the trunk.