"The Colombian Cartel is making SPANK somewhere in Liberty City, but we don't know where. And they seem to know everything we're doing before we do! We got ourselves a rat. There's a guy named Curly Bob who works the bar at Luigi's and he's been throwing more money around than he's earning. He ain't pimping or pushing, so he must be talking!"
Salvatore tells Claude that someone in the Leone Family is a rat, selling secrets to the Colombian Cartel who are manufacturing SPANK somewhere in Liberty City. Salvatore tells Claude to follow Curly Bob, a barman at Luigi's Sex Club 7 who has been spending more money than he earns at Luigi's.
Claude drives over to Luigi's and follows Curly Bob, who takes a taxi to Portland Harbor, where he meets Catalina and Miguel of the Cartel. Catalina hands Bob the SPANK, with Bob then telling them of the Leone Family's problems with the Triads and the Forelli Family. After Catalina and Miguel leave, Claude kills Curly Bob.
Curly Bob - Killed on orders from Salvatore for leaking the Leone's secrets to the Colombian Cartel.
Run over Curly Bob at full speed, don't let him fire his shotgun.
If the player manages to get a taxi and parks it behind Curly Bob's one, Curly Bob will enter Claude's Taxi instead of getting into the directed one. The mission objective will also be changed into "Take him to Portland Harbor" and the spook-o-meter won't appear. This makes the mission much easier as the player now simply needs to drop Curly Bob at Portland Harbor instead of having to tail him and risk spooking him. A Borgnine or Cabbie also works.
However, this does not always work in the mobile port of the game. Even when Claude parks his taxi behind the directed one without damaging both, Curly will sometimes get into the latter, causing the method to be useless. This situation was not fixed.
Salvatore highlights how Curly is spending more money than he is earning working at Luigi's. Curly does not sell drugs, nor does he pimp out prostitutes, therefore he must be the rat.
Salvatore informs Claude that Curly takes a taxi home every day after work, and instructs Claude to follow his taxi to see if Curly indeed is the rat. If Curly indeed turns out to be the rat, Salvatore orders Claude to kill him.
Claude running back to his vehicle.
Claude heading to Luigi's Club, where Curly Bob works.
Catalina asks Curly if he was followed and Curly says no, unaware of Claude, who was following him. Curly asks Catalina if she has his "stuff".
Catalina hands Curly some SPANK and tells him to tell them something about the Leones.
Curly tells Catalina and Miguel about the war between the Leones and the triads and Joey Leone's bad blood with the Forelli Crime Family, before noting that Salvatore does not even suspect Curly being a rat.
Catalina comments on Curly's loyalty and sarcastically says that Salvatore has nothing to worry about, before heading off with Miguel.
Claude, after learning of Curly's betrayal is tasked with killing him.
Claude, moments before running Curly over.
Curly Bob's taxi will not appear on the radar but a 'spookometer' appears warning the player if they get too close. This is the only use of a 'spookometer' in the entire game, though it reappeared in later games in the series.
Pedestrians will no longer appear in Portland Harbor after this mission.