- “The real question is, did you turn up to rescue Maria, or to get me back? Well, I got news for you! Shooting you will be a pleasure, but dating you was only business! You are muy pequeñito amigo! Throw over the cash. You have been a busy boy, but you haven't learned. I'm not to be trusted. KILL THE IDIOT!”
- — Catalina
The Exchange is the final storyline mission in Grand Theft Auto III. It is given to the main protagonist, Claude, by Colombian Cartel leader, ex-girlfriend, and main antagonist Catalina from the Cartel Mansion in Cedar Grove, Shoreside Vale, Liberty City.
Catalina recently kidnapped Maria Latore. She now wants Claude to bring $500,000 to the Cartel mansion in Cedar Grove in exchange for not having Maria killed. Claude arrives at the mansion’s gate and hands over the money to a Cartel member, having all his weapons taken away before being brought in to meet Catalina. Catalina chastises Claude for trusting her and walks off with the money, but not before ordering her men to kill Claude.
Claude is put under gunpoint by a Cartel member, but quickly escapes by punching him and taking the pistol he dropped. Claude swiftly takes down the remaining Cartel members before leaving the mansion, only to find a helicopter hovering above him which holds both Catalina and Maria. Claude follows the helicopter all the way to the base of Cochrane Dam, killing groups of heavily-armed Cartel men that gets in his way.
With Claude closing in to the helicopter, Catalina drops off Maria and a couple of her guards at the loading bay before re-entering her helicopter. Catalina's chopper fires missiles at the ground while Claude gets to Maria and kills the remaining Cartel men. Claude picks up a nearby rocket launcher to shoot down Catalina's chopper. After successfully hitting the helicopter, it crashes against the dam, killing Catalina. Afterwards, Claude and Maria walk together as they cross over to the other side of the dam.
While the credits are rolling on the screen Maria can be heard talking right before a mysterious gunshot, after which, she remains silent and is no longer heard. The news also reports the crime scene with witness Clive Denver.
- Catalina - Killed by Claude for betraying him and leaving him for dead after the bank robbery.
- Numerous members of the Colombian Cartel - Killed by Claude for getting in his way in rescuing Maria Latore and killing Catalina.
- Maria Latore - Possibly killed off-screen by Claude.
In order to complete the mission the player must:
- Get Catalina
- Follow the chopper to find Catalina
- Get Catalina
- Rescue Maria
- Take down Catalina's chopper
- This is the second mission to have a money requirement before starting. The first one being Bomb Da Base Act II.
- This is chronologically the last mission in the 3D Universe by plot order.
- This is one of the three final storyline missions in the GTA series given by an antagonist, the other two being "The Time's Come" and "Something Sensible" in Grand Theft Auto V.
- However, with the former two missions being confirmed as being non-canon, The Exchange is the only canonical mission in the GTA series to be given by an antagonist.
- As Claude punches the Cartel member, Catalina instantly vanishes from the camera view. This was, however, fixed in the mobile version.
- When Catalina says the line "Get this thing airborne!" as she boards the helicopter, the line is muted in the mobile version for an unknown reason, although the subtitles still appear when it is supposed to be said.
- The helicopter that Catalina rides is a blank-textured version of the police helicopter with no collision detection.
- Catalina's helicopter is indestructible until she drops Maria at the loading bay and boards the helicopter again.
- The helicopter can be destroyed before getting to Maria; this will remove the time limit for the mission.
- The explosions from the crashing helicopter does not affect Claude's health.
- Maria's speech during the credits was originally supposed to be longer during the beta.
- After this mission, the Colombian Cartel will carry AK-47s.
- In the 1.40 PAL release of Grand Theft Auto III, the cutscene audio has reverb and Catalina adds "and you can have your overused puta back." when ordering the briefcase.