The Big Score (GTA V)

The Big Score is a mission in Grand Theft Auto V. It is the sixth and final heist mission and the penultimate mission in the game.

The player steals a total of $201,600,000 for the Obvious, or $201,300,000 for Subtle.

Overview
Michael, Franklin, and Trevor work together to create the biggest heist of their lives, which is to steal 201 million dollars worth of gold at the Union Depository.

Obvious
Franklin uses a cutter underground to drill the building vault, planting explosives on the vault after drilling. Trevor uses a helicopter to fly the stolen gold to the county to a train while under attack by the Merryweather. Michael distracts the cops. It can be seen here

Subtle
They steal two Securicars; they took the occupants hostage and were forced to support and pose as Gruppe 6 officers. They peacefully get the gold without blowing cover. Franklin hacks the traffic lights against the Merryweather, which might disturb the transport to the destination. However, they were spotted by the Merryweather Security, and was drawn to a shootout. Afterwards, they use modified Gauntlets as escape vehicles.

Obvious
Drive the Tailgater to the Union Depository with the gunman assigned. Then you will take control of Franklin, in a HVY Cutter, underground. Use the drills by pressing a button to create a big opening on the bank vault. When the hole was created, park the cutter away for ample space. Plant explosive charges on the vault doors, then detonate them after standing back. Approach the cart, but a NOOSE team has been sent to stop you. Defend the gunman assigned against the NOOSE team by shooting at them while the gunman pushes the gokl carts. Focus on the officers, and a good gun like an Advanced Rifle with extended ammo will be better to eliminate the enemies faster. After the gunman pushes the 2nd cart, you will take contol of Trevor. Fly north of Los Santos to Blaine County, and the game will command you to switch to Michael. Michael is in a heavy shootout against the cops. Focus on health and ammo, as there are too many officers to fight, and may take 10 minutes of gunfights. Keep on killing them, and you can switch to Franklin. While advancing, a Buzzard will appear. Destroy it quickly and wisely, as it will use the rockets to kill your team. After destroying it, advance to the underground parking lot while fending off the cops. At the parking lot, an FIB team will appear, in their Grangers. Kill them faster. After killing them, get in the car and lose the cops. A 5-star wanted level may take about 5 minutes of cooling down, so find a better hiding spot, or better in the dark.

You will then switch to Trevor in a helicopter. Follow the driver assigned. However, the Merryweather Security appears in helicopters, and Lester must destroy the helicopters. Keep the helicopter steady for a clean shot, but be careful not to let the gold cart under the helicopter detach, or else the mission will fail. After destroying the helicopters, locate a train in your radar and detach the gold cart in the train car. Finally, fly to the airstrip in Sandy Shores. Mission complete. Seen here

Subtle
Get in the car after the cutscenes. Drive to the tunnel before 8:00 am. The time is shown on the lower right corner of the screen. After getting to the tunnel, wait for 2 Securicars to enter the tunnel. Drop a spike strip or Stinger before the vans leave, then drive away and wait for them to hit the spikes.

The vans' tires have deflated and stopped. Get out of the car and start pointing your gun at the windows of the vans. The occupants will be forced to get out of their vans as hostages. Another van will appear, and requested to change the tires. They will be forced to ride in the vans in order to support them. Drive to the Union Depository building underground garage, and they will park the Securicars in reverse. A cutscene will show the manager requesting an authorization ID. It was successful, now follow the manager to an elevator going down the carts containing gold. Trevor and a Gruppe 6 officer will push the carts back to the Securicars.

Get in the second van and follow Trevor as he gets out of the Depository. However, when Michael calls Franklin, the Merryweather Security had seen you stealing the gold of the Union Depository. Now switch to Franklin using a laptop to control the traffic lights of the city to escape from the Merryweather. Control the traffic lights using the assigned buttons and stop the Merryweather from spotting by turning the lights to red.

Now they have parked the Securicars. They will open the doors to transfer every packs of gold to four modified Gauntlets. However, the Merryweather show up. This engages a large shootout. Defend the crew transferring the gold. Keep focused on cover and try switching characters in order for a better shootout. Choose the best weapons, because there are many of them.

You will be switched to Franklin. Drive one of the Gauntlets and follow the rest of the crew. Focus on the route and forget the LSPD. After jumping on Rockford Plaza, the scene will slow down, showing a tanker truck in the verge of explosion after a Vapid Interceptor rolls over and crashes the tank (after this very point if you took Karim as your driver for the fourth Gauntlet, depending on his driving experiance he ends up crashing his gauntlet thus pulled out by the police and ending up incarcerated plus losing a quarter of the gold). After going to the freeway, a LSPD Maverick shows up. Don't worry on the gunners, they will just shoot when you will enter the tunnel. Drive to two trailers waiting for the four Gauntlets, including you. The LSPD failed to arrest them thanks to the two trailers.

The three will enter a Cavalcade. Drive to Michael's House. Mission complete.

Trivia

 * Depending on which route you take will changes how much money each character ends the game with.
 * There is a mission in GTA Advance that shares the same name as this mission.
 * Choosing the obvious approach will yield around $31,000,000 per character, as long as you choose a good driver to pilot the helicopter, otherwise half the score will be lost. Taking this approach is far more difficult.
 * Choosing the subtle approach will yield around $24,000,000 per character. It is important to have a good hacker; lesser skilled hackers will cause lag in the traffic lights making this part of the heist more difficult.
 * The cut of each character cannot be collected until the mission The Third Way is completed (Only if Option C - Deathwish is selected).
 * The takes of the two approaches have a difference of $300,000, because during the transferring of gold, Casey (the Gruppe 6 man) was given one bar of gold before Merryweather came.
 * The subtle approach has quite a few references to "The Italian Job", both the 1969 original and the 2003 remake. As part of the mission, you have to manipulate traffic lights to prevent Merryweather reaching Michael and the armored convoy. Another part is a high speed chase in four Gauntlets, in the end loading them at the back of two trucks, as opposed to the three Mini Coopers and loading them onto a coach from the films.
 * The post-mission cutscene features Franklin, Michael, and Trevor in their default outfits from the beginning of the game; Franklin in his repo outfit, Michael in his grey suit, and Trevor in his white shirt and sweatpants.
 * This mission could be a reference to the 1983 movie The Big Score, as there is also a police chase, a big take of money, and there is also a character named Frank.