Directive 8020, Supermassive Games’ immersive sci-fi horror entry in The Dark Pictures Anthology, features several clever environmental puzzles that blend exploration, observation, and light science. One of the most notable mid-game challenges occurs in Episode 5 during the “Drugs” chapter, where players must synthesize Diazepam (a sedative) for Anders by unlocking the chemical cabinet with the correct three-digit code. This comprehensive guide explains the full solution, including all clues, the exact code, step-by-step instructions, and tips for success.
Whether you’re progressing the story, hunting trophies like “Cat’s Out the Bag” or “Is This Decaf?”, or chasing 100% completion, solving this puzzle is essential.
Why the Diazepam Synthesis Puzzle Matters in Episode 5
In Episode 5, tensions rise aboard the Cassiopeia as the crew deals with the effects of the mysterious sample. Anders needs a sedative (Diazepam) to manage a critical situation involving Williams. The chemicals are locked in a secure cabinet, and the puzzle requires matching chemical structures from posters scattered around the medical lab to the required formula on the synthesis terminal.
Failing to create the sedative can lock out key story branches, affect character relationships, and impact multiple trophies. The puzzle is fixed on every playthrough and relies entirely on in-world clues—no trial and error needed.
Key Details:
- Episode: 5 (Drugs chapter)
- Code: 168
- Required Chemicals: Chloroacetyl Chloride, Ammonia, Dimethyl Sulfate
- Difficulty: Easy to medium (observation-based)
- Missable: Partially—related story branches and trophies can be affected
- Recommended Mode: Explorer (Turning Points for easy corrections)
Step-by-Step Guide: Solving the Diazepam Synthesis Puzzle
Step 1: Reach the Medical Laboratory
Progress through Episode 5 until you gain control of Samantha Cooper in the lab area. Anders will ask you to synthesize a sedative. Head to the chemical workstation.
Step 2: Examine the Diazepam Synthesis Terminal
- Interact with the large display/terminal screen to the left of the locked chemical cabinet.
- This shows the three chemical structures (formulae) required for Diazepam synthesis.
- Note the symbols—they do not have names displayed here, which is where most players get stuck.
Step 3: Locate and Match the Posters
Search the room for three posters or infographics on the walls that display chemical names alongside their structures:
- Chloroacetyl Chloride → Corresponds to the number 1
- Ammonia → Corresponds to the number 6
- Dimethyl Sulfate → Corresponds to the number 8
Cross-reference each structure from the terminal with the posters to identify the matching names and their assigned numbers. The order is based on how the structures appear on the synthesis screen (usually left to right).
Pro Tip: Use your scanner or Utility Strap to highlight interactive elements. The posters are clearly visible around the lab—check all walls thoroughly.
Step 4: Unlock the Chemical Cabinet
- Approach the locked cabinet.
- Interact with the keypad.
- Enter the code 168.
- This unlocks the cabinet and allows you to access the correct agents.
Step 5: Combine the Chemicals
Once unlocked, select and combine:
- Chloroacetyl Chloride
- Ammonia
- Dimethyl Sulfate
Return the completed Diazepam to Anders to continue the story.
Rewards and Story Impact
Successfully synthesizing the sedative:
- Advances the main narrative and unlocks subsequent scenes.
- Supports trophies like “Cat’s Out the Bag” (by maintaining positive/cooperative paths with Williams).
- Contributes to crew survival and relationship branches.
- Provides deeper lore about the ship’s medical systems and crew stress levels.
Common Mistakes and Troubleshooting
| Issue | Solution |
|---|---|
| Forgetting to check the terminal first | Always examine the synthesis display before hunting posters |
| Mixing up chemical matches | Carefully compare structures/symbols on posters |
| Code not working | Confirm 168 in exact order (1-6-8) |
| Missing a poster | Thoroughly scan the entire medical lab room |
| Story branch not triggering | Ensure you deliver the sedative and make supportive dialogue choices afterward |
Players often rush past the posters or fail to match structures accurately. Take your time—Supermassive Games rewards careful observation.
Best Strategies for Puzzle Success
- Explorer Mode Advantage: Turning Points let you rewind if you miss a clue or make a wrong choice later.
- Scan Liberally: Your tools highlight posters, terminals, and cabinets.
- Manual Saves: Save before entering the lab section.
- Combine with Other Goals: This puzzle overlaps with collectibles and relationship-building opportunities in Episode 5.
- Second Runs: Use Chapter Select or Story Tree for cleanup if needed.
This puzzle builds on earlier codes (like Locker Room 13576 and Food Storage 0402) by emphasizing environmental storytelling and pattern matching.
Why Directive 8020’s Puzzle Design Stands Out
Supermassive Games masterfully integrates light science-themed puzzles into the horror narrative. The Diazepam synthesis feels believable within the spaceship setting and encourages players to explore rather than guess. It also ties directly into character decisions, making your success feel impactful on the crew’s fate.
Many players report this as a memorable early-to-mid game hurdle, especially on first playthroughs.
Additional Episode 5 Tips
While in the medical lab:
- Explore all side areas for collectibles and crew messages.
- Pay attention to dialogue choices with Anders and Williams—they influence later trophies.
- Stay alert for QTEs or escalating threats in subsequent scenes.
- Link this success with power/fire control decisions from Episode 2 for broader survival trophies.
Thorough exploration here sets you up well for the game’s climax.
Conclusion: Synthesize Success with Code 168
The Correct Chemical Agents Code in Directive 8020 is 168. Examine the Diazepam Synthesis terminal, match the structures to the wall posters (Chloroacetyl Chloride = 1, Ammonia = 6, Dimethyl Sulfate = 8), unlock the cabinet, and combine the agents to create the sedative for Anders.
This straightforward yet immersive puzzle advances the story and supports multiple trophies. Save this guide, load into Episode 5, and keep your crew calm—one precise chemical match at a time.
Mastering puzzles like this enhances your overall experience aboard the Cassiopeia and brings you closer to uncovering the full truth behind Directive 8020
