Laura, the main character, found an anonoymous note written backwards. The note was about a surprise quiz, and the writer of the note knew that she wanted to do well because she wanted to go to medical school. Nobody, not even her parents knew that she wanted to go to medical school. Laura then forgets a report at home, and when she gets to school it's there, but it's typed backwards. She knew she hadn't written it backwards, no typewriter could even write like that.
(2) Who's going to catch us?
(1) I bet we're not supposed to be here
Laura threw the report in the locker, and slammed the door. She remembered that she had to get the report out for her next class, but she forgot the combination. All of a sudden, her weird neighbor, Omar, tells her to go to class, and that he'll get the locker open. He got her report and returned it to Laura. The report is not reversed anymore, so Laura wonders how he got into her locker and got the report un-reversed without knowing her combination.
No Laura, wrong way, it's a dead end!
Laura finds out that Omar can travel to the 4th dimension. She forced him to take her there, and he takes her to a place where if the creatures find you, they have to kill you. When he takes her there, she returns being reversed. Her heart is on the wrong side, everything tasted different, and her whole room was even reversed. She wants him to take her back to un-reverse her, but it isn't as easy as she thinks.
Laura has to survive a day at school while being reversed, and you can't eat because reversed food isn't delightful She ended up finding out that ketchup is the most delicious thing when you are reversed. So when her boyfriend, Pete, takes her to a secret place that they can't get out of, she sneaks into the 4th dimension to get them out, and to reverse the ketchup. If she reverses the ketchup, everyone would be able to taste how delicious reversed ketchup is. Pete becomes interested, so Laura takes him there, but she does not know how to get them back.
Laura realized that they went way farther than they should've, and soon they started hearing sounds. Those sounds were coming from the 4-space creatures. The creatures saw them, and Laura didn't want to just leave because then the creatures would be aware of their world. Laura gets Omar to come through to help them out, and luckily Omar could help them. Laura had to get through a maze as Pete was held by the creature.
They all got back to safety, and almost everything turned out fine. Later in life, Omar and Laura got married because her old boyfriend, Pete, turned out to be not a good fit for Laura. Laura became a surgeon, and Omar goes into the different dimensions to take over the current guardian. They were devoted to each other, and informed each other about their jobs.