When Karen was little she often played with her siblings, Laura and Tim, by opening doors to different worlds. They never fully understood this strange talent and had to hide it from their father, who beat them whenever they used it.
There was also a more mysterious and threatening element in their lives - the Grey Man, who followed Karen's family wherever they went and hunted their dreams.
Now, many years later, Karen lives in Toronto with her fifteen year old son, Michael. She tries to lead a normal life, tries to forget about her mysterious powers and about years of abuse she suffered at hands of her father. But the Grey Man returns, this time for Michael, who has recently manifested the same talent as his mother.
Panicked Karen does what she did all her life. She tries to hide this time with her sister Laura in a different world and pretend everything is normal. But the Grey Man finds them even then. Finally, Karen, Laura and Michael decide that their best chance lies with discovering the truth about the origin of their ability and hopefully about the Grey Man.
- Boom Town: Turquoise Beach was one of these in twenties.
- Changeling Fantasy: Karens, Lauras and Tims real parents were killed by the Gray Man and kids themselves got adopted by Willis and Jeanne. Per formula of this trope they were mistreated by their adoptive father for using their powers.
- Fate Worse than Death: What Novus Ordo did to Walker. They operated on his brain until he was nothing but obedient and lost any capacity to feel emotions. They were planning to do the same to Michael and his family.
- For Your Own Good: How Willis Fauve justified beating his children. He believed their ability could open a portal to Hell and that the Gray Man following his family was the devil.
- The Force Is Strong with This One: These who walk between worlds are able to feel other individuals with the same power. They can also smell their trail and follow them. Walker uses this ability to always find Michaels family
- Imagination-Based Superpower: People who can move between worlds are limited only by their own imagination and expectations. Thats why Laura found Turquoise Beach (basically a hippie paradise) when she was looking for her perfect world, why Tim could only enter dark and miserable places and why Michael is able to escape from Novus Ordo, despite their binding spells.
- I Want Them Alive: The Gray Man was supposed to bring William and Julia back alive. He killed them instead and got punished for it. He has the same orders for Michael and his family.
- The Multiverse: There are many alternative universes the main characters can walk between.
- Posthumous Character: William and Julia die long before events of the book. They still have a lot of impact, however, by being two of the first world-walkers created by the Defense Research Institute and parents of Karen, Laura and Tim.
- Portal Cut: How Walker kills Julia and William.
- Quirky Town: Turquoise Beach is a bohemian town full of poets, crazy writers, artists and musicians.
- Secret Legacy: Karen, Laura and Tim are children of Julia and William, two world-walkers who escaped from the Defense Research Institute to our universe. They inherited their parents powers and now Novus Ordo wants them back, along with Karens son - Michael.
- Secret Project Refugee Family: Julia and William ran away from the Defense Research Institute to our world but they were quickly tracked down by Walker. He killed them, but they managed to hide their three children. Yeas later Micheals family is hunted down the same way.
- Sibling Yin-Yang: Karen comes out as more sensible and down-to-earth than her free-spirited sister Laura and her rebellious, impulsive brother Tim. When Karen is mostly interested (or pretending she is) in a normal life, both Laura and Tim try to understand their powers and look for a world better than the one they were born in.
- Super Breeding Program: The Defense Research Institute took people with potential to open gates between worlds and breed them together. The results of this experiment were Walker, Julia and William. There are hints there conduct other similar projects as well.
- Super Powerful Genetics: Karen, Laura and Tim all share the same ability to move between different worlds. Karens son Michael inherited this power as well. Surprisingly, their parents dont show any sign of this talent at all. Thats because there is no blood relation here. However, Julia and William, their real parents, were very talented world-walkers.
- Teleporters and Transporters: Main characters can open doors to different worlds and move between them.
- Tired of Running: Karen, Laura and Michael finally get tired of running from the Gray Man and decide to find some answers in his home world. It turns about to be a trap set by Walker and Tim.
- Thicker Than Water: Subverted. Tim puts loyalty to Walker over loyalty to his real family. Justified because Tim has never experience anything good from his parents, havent seen his sisters in twenty years and it was the Gray Man who saved him when he hit rock bottom.
- What the Hell, Hero?: Laura calls Karen out on her desire to be normal, when she knows perfectly well that she is a freak and doesnt fit in. She also points out that Karen shouldnt hide the truth from Michael.
- Where It All Began: The final confrontation with the Gray Man takes place in the same universe and the same town Karen met him as a child for the first time.
- You Can Run, but You Can't Hide: Michael and his family can move between worlds, but they cant ultimately hide from the Grey Man, since he follows their scent.