Christopher, stay here in my room. I will lock it so that no one can get in or out, except for me.
Christopher Rowe's master, Benedict Blackthorn has been murdered and he is not the first apothecary this has happened to. Also, Christopher is not old enough (he is 11), so his masters shop (also him and his master's home) is taken from him.
While searching for his masters killer, Christopher discovered that his (now dead) master's shop has been ransacked, and he saw another apothecary named Nathaniel Stub (not surprisingly, he had wanted to buy the shop in the past) and his apprentice in the shop acting secretive when Christopher was looking in it.
Your former master and I were the last alchemists. Now that he is dead, I am the last one. Here is the archangles fire. Please use it well
the archangle's fire
Christopher then told the Oswyn Colthurst, the right-hand man of the head apothecary about what he saw and Oswyn told him to stay in his office in the apothecary building and locks the door. He also tells him to not go into the corridors considering that Nathaniel Stubb could be there.
Christopher uses oil of Virtriol (it can dissolves anything as strong as iron or weaker) to burn the lock and escape, but then found at the door there are two men with axes that want to kill Christopher. They chase him around the courtyard until Christopher escapes.
the archangle's fire
Christopher decodes a code he found in his masters shop and it said "Issac has the key". Issac is the owner of a book shop and was best friends with Benedict Blackthorn. Christopher goes to Issac and Issac reveals to Christoper that Issac and Blackthorn are alchemists and the only ones left. He also gives Christopher the recipe for the archangle's fire, the ultimate weapon that some one has been killing apothecaries for. Issac had been told by Benedict to give Christopher this when Christopher came to Issac (after he cracked the code).
Christopher decides to right a note to Lord Ashcombe that he has an idea to trap the leader of the cult and he rights a note to Oswyn (who Christopher realized to be the actual villain. Nathaniel Stubb was merely a pawn and is now dead) that he will surrender and tell him the recipe for the archangle's fire.
Lord Ashcombe gets injured and all of his soldiers are killed by Oswyn's soldiers. Christopher was forced to give up his recipe for the archangles' fire. He then brings Ashcombe and Christopher down into the secret testing lab under the angle statue.
Oswyn underestimated the power of the archangles fire and used the fire without controlling it. He burns in the fire but Christopher gets Lord Ashcombe and himself to cover.
They escape and Christopher purposely burns the recipe for the archangle's fire. Christopher gets his shop back and is told he will soon have another master.