In The Merlin Conspiracy, Jerome Kirk is a petulant, disgruntled minor magician who is up to no good. He is the estranged husband of Dora Dimber Hyde, and he phones her up to say that she must let his son Toby visit him.
Protagonist Nick Mallory encounters Kirk when he goes with Maxwell Hyde and Toby on the obligatory visit. There, they find Kirk's house dark, dusty and cluttered, and Kirk himself not much better. Not a part of the main conspiracy of the book's title, he has joined in with other discontented wizards and witches who feel that they don't get enough respect from the magically talented elites. As a result, they are being supplied with illegal salamanders, which they torture to bring out a burst of magic. Kirk is working to recruit others to the cause.
In talking to Nick and trying to persuade him to join this nameless association of miscreants, he mentions that he's agreed to live in an area that is full of the old magics. This doesn't register with Nick until he slips off and finds himself on the chalk hillside above Kirk's house. There he encounters a very magical being, and gets properly terrified by it. Luckily, no one ends up joining Jerome Kirk, which was just as well.