When Katie and her twin cousins step into a mysterious rowboat, Matt and his three buddies run to their rescue. But they are too late, and soon the seven are swept back in time, to Boston in 1776. The British have occupied the city, and George Washington and his troops are planning an attack. While the boys are trying to find their way to the girls after being separated, the boys become entangled with patriot spies.
Meanwhile, the girls have been taken in by the wealthy Hewson family, whom they soon discover are "redcoats"! Now, on opposite sides of the war, they are confronted firsthand with realities that tore friends and families apart during the American Revolution.