Iodine

Iodine is the 17th clue. It is a Janus clue and was located in Hollywood, U.S.A.

History
The Janus author of the novel Frankenstein, Mary Shelley, hid this clue within her novel. The book was placed in the Janus Hollywood stronghold. However, nobody else was able to discover the clue and solve Mary Shelley's puzzle.

Iodine
Iodine is a chemical that is commonly used in antiseptics. It can also be used for purifying water as well as being used in salt.