The Sims 4

How to Solve The Sims 4 StrangerVille Mystery Storyline

Requires The Sims 4 StrangerVille
Presented by EA Game Changers

This guide contains spoilers from the storyline. In this guide we’ll tell you how to open the secret lab door, how to collect pieces of evidence, collect the infection scanner, get through the purple dust in the basement and how to save StrangerVille from the infection. If you want to remove the story and just want to play or skip certain parts, you can also use cheats.

Preparing your Sim to solve the mystery in StrangerVille

Before starting your story in StrangerVille you should equip your Sim with the right Aspiration. Pick the StrangerVille Mystery aspiration (can be found at Location in the aspirations menu). This will help you get the steps you need to take to solve the mystery.

Now let’s start your story in this mysterious place.

Part 1 – StrangerVille

Welcome to StrangerVille: “The Only thing stranger than the people is the flora!”

Soon after moving in, the town’s slogan is starting to make sense to you. Some of the locals are acting a bit suspicious and there’s a large number of Military and Scientists in town.

Try asking people about StrangerVille. They might be able to shed some light on this strange situation.

Ga around town to talk to your local neighbors, scientist and military about StrangerVille. This will give you information about the things that are happening in this town. Go to the Secret Lab to examine the door. This will give you information about how to open this door.

Obtain the keycard to open the secret lab door

How to open the Secret Lab door

You’ll need a Keycard but you’ll have to walk through some other steps first. In order to get a Keycard you’ll first need to find evidence so you can convince scientists and military that you are aware of the things that are happening around town. When you’ll find 15 pieces of evidence you can compile a StrangerVille Secret Dossier and give it to them. You also need a slightly higher relationship status with them to convince them to hand you the Keycard.

Another option is to reach level 5 in the military career and the Keycard will be send to you almost immediately to your mail. You can also befriend the store owner next to the crash site and buy it from him.

How to find pieces of evidence and collect the Keycard

It’s time to find clues to compile a dossier about the weird things that are happening in StrangerVille. You’ll need 15 pieces of evidence before you can do anything with the evidence. So start searching around in the Secret Lab.

You can find evidence all over town. You don’t have to wait until the clues respawn in the Secret Lab so start digging around in the library or ask scientist, military or conspiracy theorists.

  • Take pictures
    Take photographs of a plant and the door to the secret lab to obtain one piece of evidence.
  • Plant bugs on local Sims, Scientist or Military
    Set up a listening device at your home. You can now order 51M5 Spy Bugs when you click on the listening device or you can visit the little shop near the crash site to get them. Go around town to plant them on random strangers. Return home to listen to their recordings.
  • Go around the Secret Lab searching for piles with documents
    You’ll find piles with documents all over the secret lab, they will respawn eventually when you find them all.
  • Hack into lab computers (requires programming skill level 3)
    There are 4 computers in the lab your Sim can hack. Your Sim must have a programming skill of at least level 3 before unlocking this interaction.
  • Search the library
    Click on the bookcase and search StrangerVille Archives.
  • Befriend scientists, military or conspiracy theorists
    If you befriend them you can request evidence from the secret lab or for StrangerVille Mystery.

After you’ve collect all the evidence you can compile a dossier. Show them to scientists or military you are friends with to get the Keycard. Go to the Secret Lab and use the Keycard on the lab door.

Part 2 – The Bloom Begins

Leaving the Secret Lab you can’t help but notice the sky has shifted to an eerie color. Something has changed in StrangerVille, and not for the better. Opening that lab door must have released some kind of toxin into the air.

You will need to find a way to protect yourself from the toxic spores in the Secret Lab. Try talking to people around town to see if they know of anything that might help.


Getting through the purple spore dust in the basement

To get to the next level in the basement you’ll need 2 things: A breathing filter and a hazmat suit. In order to get the breathing filter you now need to obtain infection profile data. You can construct this by gathering 15 spore clusters. Spore clusters can be found using the Infection scanner. Let’s walk through this step by step.

  1. Obtain the Infection Scanner
  2. Gather 15 Spore Clusters
  3. Construct Infection Profile Data
  4. Get the breathing filter
Fight military to obtain the Infection Scanner

Obtain the Infection Scanner

Go to the bar in StrangerVille. You’ll find a lot of military walking around that can give you the scanner. First you need to convince them to give it to you.

If you want to impress them you’ll need a high enough fitness skill to show them you physical strength by doing push ups. You can also convince them by seducing them but you’ll need a good (flirty) relationship in order for it to work. If you’re choosing to fight them there’s a small chance you can win but it will decrease your relationship massively when you do. If you want to make sure you’ll get the scanner you can bribe a military for 750 Simoleons you’re friends with. If you are a military yourself and reached rank 5, I highly suggest to use the pull rank interaction. This will guarantee that you’ll get the scanner.

Find Spore Clusters with the Infection Scanner

Gather 15 Spore Clusters

Now you’ve got the scanner you’ll need to find spore clusters. The infection scanner can be used to reveal spore clusters by clicking and scanning on the ground. Try scanning areas with a high concentration of spores like the Secret Lab. You have 4 scans before the scanner needs a recharge so head to the Secret Lab because you’ll find much more of them with each scan.

Start constructing Infection Profile Data with 15 Spore Clusters

Construct Infection Profile Data

After you gathered 15 spore clusters you can click on the machines in the basement of the secret lab and start constructing Infection Profile Data. After you’ve completed it you’ll need to take the Infection Profile Data to a scientist. This is needed to construct a breathing filter you’ll need to get deeper into the basement.

Get the breathing filter

Give the Infection Profile Data to a StrangerVille Scientist you are friends with to construct an effective Spore Filter. You can find them hanging out in the local Library. After you’ve succeeded you’ll get the breathing filter into your mail. You’ll still need a hazmat suit in order to go through the purple dust in the basement.

You can find the shop near the crash site

Obtaining and completing the Hazmat Suit

Now we need to find a way to get through the spores to the next lab door in the basement by obtaining a hazmat suit that we need to combine with the breathing filter. Go to the shop next to the crash site and talk about StrangerVille to unlock a new option in the Secret Inventory. You can buy it for 1000 Simoleons.

After you’ve obtained the hazmat suit and received the breathing filter from your mail you can go to your inventory and click on them and combine the two.

Put on the modified hazmat suit and proceed to the next level of the basement in the Secret Lab. Walk all the way to the end and open the door…

Part 3 – Stop The Infection

You’ve discovered the source of the infection plaguing StrangerVille: an enormous “Mother” plant buried in the base of the lab. The only way to get the town back to normal is to defeat the vile creature!

Find a cure for the infection and assemble a team to destroy the Mother Plant.

You’ll get a few interactions with the mother plant but they won’t do anything serious. The only way to save the village is to create a vaccine and gather other Sims to help you defeat the Mother Plant.

Test vaccines on possessed Sims

Creating a Vaccine

First of all you’ll need to create a few experimental vaccines so you can test it on other Sims. You’ll need 5 Spore Clusters (found when scanning the area with the Infection Scanner) and 1 Bizarre fruit. Bizarre fruit can be found when nurturing purple flowers in the world (you can harvest them after) or can be bought at the shop near the crash site.

Go back to the lower levels of the basement to create the experimental vaccine on the Chemical Analyzer. Make sure you’ll collect enough to create 3-4 samples because some have a different outcome. Now search around the neighborhood for possessed Sims. Use the ‘Test Experimental Vaccine’ interaction to try and cure them. After you cured one of them you’ll need to go back to the lab to create the actual vaccine. Click on the Chemical Analyzer to Convert the Experimental Vaccine. You’ll need maybe 10 of them for other Sims so you can gather up a party to fight the Mother Plant and it will be helpful when fighting this thing.

Handing out Vaccines and recruit Sims

Go around town to administer Infection Vaccine to other Sims. They will be temporarily immune to the possessed buff so they can help fight Mother Plant. Make sure you’ll pick the Sims you have the best relationship with so they will accept your request to fight her.

Tip: Take a few vaccines with you to defeat the mother plant

Defeating the Mother Plant

Bring some extra vaccines to fight the Mother Plant, this will make the fight a bit easier. Go into the Secret Lab and return to the Mother Plant. You don’t need to bring your recruit just jet. Just click on the Mother Plant and choose to fight with your recruits and they will come running down to you. Take at least 2 recruits with you and bring a few vaccines.

Make sure you bring enough recruits to defeat the Mother Plant

Tactics to defeat the Mother Plant

The first bar is the health bar from Mother Plant. The second bar you’ll see the team infection level. If the Infection bar is at 100%, you will lose.

Try balance the interactions. Use the Mega Spray and Throw Infection Vaccine when available. Minions will start a fight with your recruits so they can’t help you at the moment. When the room is full of minions you can use the group command; War Cry. This will back down the minions a bit. Infection level low? Use the Charge! Command to boost damage. Infection level almost at 100%? Use the Take a Breather command to lower the infection bar.

  • Mega Spray
    This will deplete the health bar a bit more as the standard interaction.
  • Trow Infection Vaccine
    This will deplete the health bar from Mother Plant.
  • Group Command: Be Careful
    Your team resist the Infection a bit more, but deals less damage.
  • Group Command: Charge!
    Your team deals more damage, but becomes infected faster.
  • Group Command: Take a Breather
    Your team heals some of their Infection, but does no damage.
  • Group Command: War Cry
    Your team scares off the Mother Plant’s minions, but does less damage.
  • Retreat
    Stop the encounter and lose from Mother Plant.

After you defeated the Mother Plant you’ll be able to resurrect her. All you need is one Bizarre Fruit. After you resurrected the Mother Plant you’ll be able to ask for Bizarre Fruit from her. If you want you can even befriend her by doing friendly interactions and request certain things as: career success, energy, life extension and riches.


You’ll get a Sampling of the Mother for you to display at your lot after defeating her. You can find this item in your family inventory when in build/buy mode.

Part 4 – A Little Less StrangerVille

With one last screech the Mother Plant collapses. Returning home you notice that things are beginning to return to normal. The Bizarre Plants are subsiding and the infected are waking up from their nightmare. StranerVille owes you a huge dept. You are a Hometown Hero!

You have defeated the Mother Plant and returned StrangerVille to “normal”! You can return to the Mother Plant at any point to reawaken her. Once resurrected, you can have her set the Infection Level to your desired Strangeness. This will allow you to replay the story with other families.

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  1. i sold the infection scanner when i was done with it then i found out i need it for the vaccine. No scientist or military person can give it to me. How can i get it back without restarting??

  2. how do you use the fighting tactics? when i click on her while im fighting her it just has an option fo “retreat”

  3. how do you use the fighting tactics? when i click on her while im fighting her it just has an option to “retreat” ?? pls help! ive tried to defeat her 5 times and and i keep losing! it says to recruit more people (i have 4) but it will only let me select 3

  4. You can requisition a key card when you reach Military level 5 career but only after you examine the door at the lab

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