“So, if we're gonna do some tunneling to the vault, we need a drill. And not just any drill. Take whatever you imagined, multiply it by the size of a building, and you're somewhere close. The only one in-state is all packed up on a flatbed at a construction site. I'll ping you the GPS now. Get it to the sewers, and I'll take care of the rest.”
— Lester's briefing.
Lester informs the player that they must steal a Flatbed with a Cutter on it from Davis Quartz to be able to drill a tunnel to the vault from the sewer. After arriving and stealing the Flatbed, the workers nearby become hostile and the player receives a two-star wanted level. After escaping the police, the player must drop off the truck at the sewer access point to complete the mission.
“That's the one, pretty big, huh? O-okay, you've got from now until the sewers to drop every innuendo you can dream of. As long as you lose the cops by the time you get there, I don't care.”
— After stealing the Flatbed.
“Do you know how many drills there are in the world that are capable of tunneling through the titanium-reinforced foundations of the world's most secure underground vault? Two. And unless you fancy a trip to Siberia, we'll be liberating our from a convoy en route to a construction site right here in San Andreas. Thing is. it's big. You'll need to commandeer whatever vehicle they're using to move it around.”
— Lester's briefing.
Lester informs the player that there is a convoy transporting a Cutter to a construction site and that they need to commandeer it by any means necessary. This convoy can be in location such as East Joshua Road in Blaine County. Similar to the Construction Site mission, the player must steal the Flatbed with the Cutter on it and transport it to the sewers, then the mission will be complete.
“Pretty big, huh? Now get your incredibly witty penis jokes out of your system and get ready to attract a whole lot of police attention when you make your play.”
— When approaching the truck.
“I need this thing on-site, without a police escort. Lose the cops, and get it over to the sewers.”
— If the player obtains a wanted level.
GTA Online The Diamond Casino Heist - Tunnel Boring Machine Aggressive - Solo