It wouldn't have even shown up as an unknown substance.

He can also use the same compartment to analyze unknown substances.

Next to the chalk mark he'd made on the wall was a black design in some unknown substance.

I took the envelope out and asked him if he could test an unknown substance for me.

Then he realized that his right ear was full of an unknown substance.

The video shows the band running away from an unknown substance that made their heads expand.

According to the doctors, he was subject to intoxication with an unknown substance.

That still did not tell you how much of the unknown substance you had.

"And were you able to identify the two unknown substances in the killer's blood?"

On the way back to his barracks, the boy explored this unknown substance.