The Diamonds are featured in Grand Theft Auto IV, The Lost and Damned and The Ballad of Gay Tony wherein they are involved in many scenarios also involving the protagonists, Niko Bellic, Johnny Klebitz and Luis Fernando Lopez as well as many others. Detailed below are the many different scenarios that take place involving the diamonds and the different people that gain possession of them each time. The diamonds are the main purpose which led to the Impossible Trinity in GTA IV and Diamonds Forever in TBOGT achievements/trophies.
Below explains how the diamonds went around Liberty City, who was involved with them and why.
The cook smuggled the diamonds into Liberty City by hiding them in a cake mixture. They were brought in along with Niko Bellic aboard the Platypus. Eventually, Maisonette 9 owner Anthony "Gay Tony" Prince, his boyfriend Evan Moss, and bodyguard/business partner Luis Fernando Lopez met with the cook to buy the diamonds. Ray Boccino however, having learned of the diamonds, sent Johnny Klebitz and The Lost MC to crash the meet and steal them.
After buying the diamonds, Luis noticed Johnny and the bikers approaching and pushed Tony into a limousine, while shouting to Evan, who was holding the diamonds, to get them to Maisonette 9. Johnny sent numerous Lost members after Luis and Tony while he chased Evan. Luis and Tony managed to fend off the bikers, but Evan was caught by Johnny and killed, and the diamonds were taken. Johnny followed Ray's orders to hide the diamonds in two trash bags, which would later be collected by Niko Bellic, Luca Silvestri and his crew while disguised as trash collectors.
Niko left Luca with the diamonds as instructed, but then Luca and his crew plotted to steal the diamonds and flee to Las Venturas. Niko soon caught them before they left and killed them all in Middle Park, before taking back the diamonds and returning them to Ray.
Eventually, Ray found a buyer for the diamonds in the form of Isaac Roth and the Jewish Mob. He sent Johnny and Niko to do the deal with Isaac. Niko took the diamonds to the Libertonian Museum where Johnny would meet him. Ray's plan was for them to successfully sell the diamonds, with Johnny and Niko each taking half of the profits.
Unfortunately, Luis Lopez ambushed the deal after learning what was going down, shooting and killing Mori Green. This sparked chaos in the museum, and Johnny snatched the cash, while Isaac grabbed the diamonds. Both Niko and Johnny fought through the Jewish Mob and escaped, but Niko left with nothing. Amidst the riot, Luis caught Isaac and knocked him out, retrieving the diamonds. He then also escaped and gave them to Tony, who secured them in his safe.
Because Johnny stole the money, Ray sent Niko to kill Johnny's best friend, Jim Fitzgerald, after failing to do so himself. Johnny was then attacked by numerous groups of hitmen but managed to survive, only to learn that Jim had indeed been killed. Johnny was then advised by acquaintance; congressman Thomas Stubbs to stay away from Ray, as Stubbs correctly predicted that Ray would be either dead or in jail within a month.
Isaac Roth, having regained consciousness in the museum, fled to the Majestic Hotel and began falsely accusing Ray of setting up the deal in order to keep both the diamonds and the money. Isaac threatened to have Ray killed, so Ray promptly sent Niko to the Majestic to finish off Isaac and the Jewish Mob. After doing this, Niko refused to do any more work for Ray.
Ray's boss, James Pegorino, soon came up with a plan to get the diamonds back from Tony and Luis. They used their small time associates, the McRearys, and Niko to kidnap Tony's friend Gracie Ancelotti and hold her for ransom to coax Tony into giving up the diamonds for Gracie herself. After the Ancelotti's failed to get Gracie back by force, and with Luis and Tony facing death threats from Gracie's father, they gave in and arrived to exchange the diamonds. Niko and his friend Packie McReary met with Luis and Tony on Charge Island. The deal would have gone to plan if not for the interruption of Bulgarin, who seeked to reclaim his diamonds which he believed Luis had stolen and also to kill Niko, his former employee.
Bulgarin ordered his men to attack the exchange and kill everyone. Luis, Tony and Gracie quickly fled the scene, but Niko and Packie cut down many of Bulgarin's men and chased the one holding the diamonds. When Niko and Packie cornered him, he intentionally dropped them into a waste truck to ensure that nobody could have them, reasoning that Bulgarin would have later killed him if he was to give them up. Ultimately, Niko and Packie left empty-handed.
A short while later, Luis was walking through Meadows Park to meet with Tony, shortly after killing Bulgarin aboard his private jet. He accidentally bumped into Jerry Kapowitz, who fell to the ground knocking over a trash bin. After apologizing, Luis continued on, but Jerry noticed that amongst the split trash, lied the small pouch of diamonds. He examined them before running off with excitement.
According to a Liberty Tree report, over 100 people contested Jerry and claimed ownership of the diamonds, but Mayor Julio Ochoa finally allowed Jerry to keep the money made from selling them. He later bought a mansion in Alderney, contrary to reports that he planned to move to Vice City and open a gun and liquor store.
Note the following missions are been sorted in chronological order of the timeline.
- Opening cutscene of GTA IV.
- Diamonds in the Rough (TLAD) and Frosting on the Cake (TBOGT)
- Taking in the Trash (GTA IV)
- Meltdown (GTA IV)
- Museum Piece (GTA IV), Collector's Item (TLAD) and Not So Fast (TBOGT)
- Diamonds Are a Girl's Best Friend (GTA IV) and Ladies Half Price (TBOGT)
- Departure Time (TBOGT)
- Mentioned on Weazel News (radio).
- Everybody who touched or held the diamonds besides Niko, Luis, and Tony have been killed. Ironically, Jerry Kapowitz was not involved in any way, and never even knew of their existence, but was eventually the one to have them for himself.
- Where the diamonds ended up is not chronologically correct. On the Liberty Tree website the diamonds were supposedly heading to the dump (after which one of Bulgarin's men threw them onto the back of a truck). However Jerry Kapowitz finds them in the trash at the Monoglobe in Meadows Park, either they were somehow transported to the bin, or it is a minor retcon.