Casey is a typical teenage girl with a crush on Nate, the cutest athlete at school. She's also a time traveler, or "tripper", who at a moment's notice is transported to Massachusetts 1860. Her situation gets more complicated when, while touching Nate during one of her episodes, she takes him along on her trip. Their relationship changes under the pressures of living in 1860s America - hard work, racial tensions and the insecurity of never knowing when they'll be called back to present day.

Interwoven in the light-hearted teen romance is a history lesson on life before the Civil War, when slavery prevailed in the South and mixed attitudes in the North had yet yielded to the call of war. Flash forward 100 years and readers get insight to the Civil Rights movement another of Casey's travels. Strauss skillfully weaves these 'trips' into the story through events and characters. She also presents a side story of Casey's parents' separation that aligns with other characters coming together and falling apart.

Clockwise is a light, quick read that mixes a surprising amount of history into a teen romance story.