I received this book in exchanged for an honest review. I really like this series. The 2nd book wasn't as good as the first in my opinion, but I still really liked it. The story was good though, however I didn't appreciate the cliffhanger ending, it felt a bit rushed and incomplete almost like the book doesn't stand alone. A pet peeve of mine is that each book in a series should stand alone with a distinct ending, I just really don't like cliffhangers.
On to the actual story, Illusion picks up where Possession left off with Constance trying to figure out what being a necromancer really means. She is walking the fine line of protecting the family secret, helping her mother, and still trying to keep some normalcy with her dad, and failing miserably at all of it. Things at school are strange as Queen Bee Seline is no longer on top after her antics at Homecoming, Mr. Ransom still gives Constance the creeps, and something is up with Greta. Constance is trying to still be a normal teenager and tutor Seth at calculus by day, and at night she is trying to learn how to banish naughty spirits back to where they belong. As the book progresses they determine who the dark necromancer is and come up with a plan to try to stop him and his evil plan with Seline and Greta in tow. Greta finds out she has a poltergiest attached to her from her previous run in with that "aromatherapy" candle from book 1 that they have to banish before someone gets really hurt, and Seth finds out what is really going on with Constance. As things get more dangerous Constance starts to come to terms with her "powers" even if her mom doesn't accept that there is another way to do things. Constance starts to take things into her own hands to try to draw out the dark necromancer and get some answers. The whole Jerome clan is in danger and Constance is determined to stop the dark necromancer from hurting her friends and family.
Overall I've really enjoyed this series thus far and I'm anxious to find out what happens next. I really like the different subject matter on this one. Necromancy isn't something you see often and I like Oldham's writing style, so much so I've downloaded some of her other books. I highly recommend the series, it is a good entertaining read.