Which poison/substance test should you run on Caleb’s hair in the Mysterious Ways case in Chinatown Detective Agency?

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The Mysterious Ways case is one of the most interesting in Chinatown Detective Agency. First, you must uncover the last patient files on Caleb while Tiger Lilly distracts the doctor. Then, you’ll discover that he was suffering from some sort of ailment before he died. Naturally, everyone suspects poison, and luckily Sammy has some hairs that you can test for poisons and substances. The catch is that you only have enough hair for two tests, so you need to get this right. This guide explains which test you need to run so you don’t waste anyone’s time.

There are twelve poisons and substances that you can test for, but you can’t go through them all using trial and error when you’re limited to only two tests. So instead, you need to refer back to Caleb’s symptoms when he visited the doctors. If you didn’t write them down, we can confirm that he was suffering from muscle pain in the thighs and gastrocnemius and plantar numbness. He also experienced some loss of hair, but not a lot, it seems. If that’s enough to help you figure this out, solve the puzzle before reading on.

We found the correct substance used to poison Caleb, Thallium, by searching for the symptoms that each of the substances you can test for presents with. Thallium is the only one that mentioned a numbness in the plantar, the tissue connecting your heel to the front of your foot. The red herring here is the hair loss because while Thallium can cause that, it’s the plantar numbness that points to this being the method through which Caleb was poisoned.