The Corridor

You work for a organization known as “T.D.A”, or “Threat Detection Agency”. You have been ordered to go to this place known as “The Corridor.” They want you to go here because apparently there has been a threat detected, a strange creature capable of making you not exist in the fraction of a second. This creature is made of a strange material beyond human comprehension, but sometimes it leaves behind this material while in the act of moving. You have been ordered to collect this so T.D.A can study it.

Oh, and it can shapeshift.