Sera Froste is Dak Smyth's best friend. She is a genius in Science, and has a particular love for Physics and Science. She experiences Remnants that are said to be caused by the Great Breaks in History.
She is a classmate of Dak, who is also her best friend. When they went to a museum as a class trip, there was a strong earthquake caused because of a Great Break in History. Later, she was experiencing a Remnant; from a barn she expected to see two people emerge she thought she should know. When she went to Dak's house, they went/broke into Dak's parents' laboratory and found the incomplete Infinity Ring that still lacked a missing piece. When she was able to find the missing piece and make it work, she decided to tell Dak's parents and test it. Sera was then able to bring them back to the time of the Revolutionary War with the completed ring. But, later, when they went back to present time, Dak's parents were missing and the Hystorians (Founded By Aristotle) brought the two of them to their Headquarters where they met Riq, Brint, and Mari. Sera, along with Dak, were disgusted by the SQ's actions and agreed to help the Hystorians. Their mission became to go back in time, stop the Great Breaks, the SQ from seizing power, and the Cataclysm from destroying the Earth. In the last book, Eternity, when Riq takes them to the island of Santorini, she and Dak were horrified to see that they had been cloned. Sera gets the famous dog, Laika at the end of the book.
- Her name can be spelled with two elements: Se (Selenium) and Ra (Radium), as shown in Divide and Conquer