Best friends Shelby and Cyd gain the unpredictable power to travel back and forth in time when one of their friend Barry's science inventions goes awry. With their newfound power, the teen besties try to fix the mishaps that spoiled Shelby's plans to ask her crush Cameron out to the school dance.
When Cyd and Shelby are having trouble studying for a difficult history test, they decide to jump ahead in time and nab the test questions. Meanwhile, Barry and Naldo find themselves in a hair-raising situation when they try to figure out how to make Barry’s invention replicate time travel.
When Cyd tries to plan a special thank you for the Marcus family, Shelby steps in to help with hulu dancers, a rock band and jugglers and everything somehow leads to a big misunderstanding and a huge kitchen disaster.
Cyd and Shelby travel back to relive one of their favorite memories from middle school, but the moment winds up being totally different than what they both remembered. Now, they begin to question everything that happened on that particular day.
When Cyd and Shelby attempt to change the past so that Barry can meet his childhood science hero, they travel to a period where Naldo and Barry are rock musicians instead of scientists.
Cyd and Shelby discover a major clue to the future lab memory and it is somehow tied to Barry's Science mentor Janet Smythe, who also employs Shelby's dad.
When the girls discover inventor and GDD CEO Janet Smythe is behind the future lab, they decide to fight back and travel to the past to stop Janet from starting the corporation. Their plan seems to work until they realize they also stopped other major events from happening in their lives, including them living together and Barry and Marci falling for each other.
Things spin out of control when Cyd travels back to Christmas the year before to try and figure out the perfect gift for Shelby. Meanwhile, Barry and Naldo's Winter Wonderland experiment sparks an elf war with Bret and Chet leading the charge.
When Shelby's adventurous Grandma Rita comes to visit, the girls learn time travelers were responsible for setting up Shelby's grandparents and they jump to the 1950s to investigate.
