Monkey Business

Key takeaways

Prepare before the opening marker and treat each objective update as a checkpoint.

• Primary goal The protagonists infiltrate Humane Labs from the sea, steal a nerve agent, and extract it by helicopter.
• Protect mission-critical assets Avoid unnecessary vehicle damage, friendly fire, or abandoning a required target outside the objective radius.
• Use protagonist abilities Use Franklin for precision driving, Michael for controlled gunfights, and Trevor for high-damage combat whenever the mission makes them available.
• Do not rush the final marker Clear pursuit conditions and keep required characters or vehicles together before entering extraction.

Overview

The protagonists infiltrate Humane Labs from the sea, steal a nerve agent, and extract it by helicopter.

The protagonists infiltrate Humane Labs from the sea, steal a nerve agent, and extract it by helicopter.

This Story Mode mission advances the protagonists’ connected storyline. Some neighboring missions can become available simultaneously, so the exact play order may vary.

The walkthrough below separates travel, setup, combat, pursuit, and extraction checkpoints so a failed section can be diagnosed without repeating the same mistake.

Characters in this mission

• Michael De Santa
• Trevor Philips
• Franklin Clinton
• Dave Norton
• Steve Haines

Where this sits

Requirements and recommended loadout

Enter with mission-appropriate ammunition, armor, and a vehicle that can survive the opening travel phase.

• RequiredComplete the preceding story unlocks
• RecommendedFull body armor and stocked ammunitionParticularly valuable for missions marked moderate or hard.
• RecommendedAccurate mid-range weaponA rifle or stable automatic weapon handles most outdoor gunfights.
• OptionalClose-range backupUseful inside buildings, alleys, and vehicles.
• RecommendedSave the relevant protagonist abilityUse it for the most difficult chase, driving, or combat checkpoint.

Objectives

1. Take the boat to the offshore insertion point
2. Dive and cut through the underwater grate
3. Move through the cooling tunnels into the laboratory
4. Use the stun gun and stealth to pass scientists and guards
5. Reach the containment room and collect the nerve agent
6. Fight through the alerted security teams
7. Carry the container to the loading area
8. Use Trevor and the Cargobob to extract the container
9. Deliver it to the designated airfield

Detailed walkthrough

1. 01

   Take the boat to the offshore insertion point

   Take the boat to the offshore insertion point

   Take the boat to the offshore insertion point. Approach from the safest side, clear immediate threats, and wait for the possession or collection confirmation before moving to extraction. Once the checkpoint registers, immediately orient toward the next marked objective.

   TipBefore triggering the opening marker, restock armor and ammunition if the mission is expected to involve combat.

   Checkpoint
2. 02

   Dive and cut through the underwater grate

   Dive and cut through the underwater grate

   Dive and cut through the underwater grate. Follow the marked route and wait for the objective prompt to update before leaving the area. Once the checkpoint registers, immediately orient toward the next marked objective.

   Checkpoint
3. 03

   Move through the cooling tunnels into the laboratory

   Move through the cooling tunnels into the laboratory

   Move through the cooling tunnels into the laboratory. Follow the marked route and wait for the objective prompt to update before leaving the area. Once the checkpoint registers, immediately orient toward the next marked objective.

4. 04

   Use the stun gun and stealth to pass scientists and guards

   Use the stun gun and stealth to pass scientists and guards

   Use the stun gun and stealth to pass scientists and guards. Approach from the safest side, clear immediate threats, and wait for the possession or collection confirmation before moving to extraction. Once the checkpoint registers, immediately orient toward the next marked objective.

   Checkpoint
5. 05

   Reach the containment room and collect the nerve agent

   Reach the containment room and collect the nerve agent

   Reach the containment room and collect the nerve agent. Approach from the safest side, clear immediate threats, and wait for the possession or collection confirmation before moving to extraction. Once the checkpoint registers, immediately orient toward the next marked objective.

6. 06

   Fight through the alerted security teams

   Fight through the alerted security teams

   Fight through the alerted security teams. Move from cover to cover, remove exposed or elevated shooters first, and do not advance until the current flank is secure. Once the checkpoint registers, immediately orient toward the next marked objective.

   Watch outA failed push can expose the mission vehicle or protagonist to concentrated damage; reset behind cover instead of forcing progress.

   Checkpoint
7. 07

   Carry the container to the loading area

   Carry the container to the loading area

   Carry the container to the loading area. Follow the marked route and wait for the objective prompt to update before leaving the area. Once the checkpoint registers, immediately orient toward the next marked objective.

8. 08

   Use Trevor and the Cargobob to extract the container

   Use Trevor and the Cargobob to extract the container

   Use Trevor and the Cargobob to extract the container. Follow the marked route and wait for the objective prompt to update before leaving the area. Once the checkpoint registers, immediately orient toward the next marked objective.

   Checkpoint
9. 09

   Deliver it to the designated airfield

   Deliver it to the designated airfield

   Deliver it to the designated airfield. Follow the marked route and wait for the objective prompt to update before leaving the area. Remain in the final marker until the mission-complete transition begins.

   Checkpoint

Difficult sections and useful strategies

Completion checklist

• Take the boat to the offshore insertion pointCheckpoint 1
• Dive and cut through the underwater grateCheckpoint 2
• Move through the cooling tunnels into the laboratoryCheckpoint 3
• Use the stun gun and stealth to pass scientists and guardsCheckpoint 4
• Reach the containment room and collect the nerve agentCheckpoint 5
• Fight through the alerted security teamsCheckpoint 6
• Carry the container to the loading areaCheckpoint 7
• Use Trevor and the Cargobob to extract the containerCheckpoint 8
• Deliver it to the designated airfieldFinal completion condition

Failure conditions and checkpoints

• A required protagonist, ally, or protected target dies.Restart from the most recent mission checkpoint.
• A mission-critical vehicle is destroyed, abandoned, or leaves the playable route.Use the restart option rather than continuing in an unmarked replacement.
• The target escapes or a timed objective expires.Prioritize route discipline and the primary objective over optional combat.
• The player is wasted or all shared team lives are exhausted.Story Mode reloads the latest checkpoint.

Rewards and aftermath

• Mission completion and progression
  Unlocks the next related story activity, contact, property, or preparation where applicable.

Sources and verification

• GTA Base — GTA V missions list and walkthrough index — verified 2026-08-04 — GTA Base
• GTA V Wiki — Story Missions — verified 2026-08-04 — GTA V Wiki
• Codex model knowledge — detailed step expansion pending editorial gameplay review — Internal editorial