The TARDIS arrives in Scotland just after the battle of Culloden.  The Doctor to help the Highlanders' leader, Colin McLaren.  Polly goes with the Kirsty, the Laird's daughter, to get water when the Redcoats take the Doctor and the Highlanders cative.

Grey, a man who sells prisoners into slavery in the West Indies, takes the captives.  Polly and Kirsty convince the Redcoat lieutenant to help them.  The Doctor is able to get arms to the Highlanders on board ship.  The Highlanders take the ship and return it to its rightful owner who then agrees to take them to France.  Jamie McCrimmon decides not to leave with his clansmen and joins the TARDIS crew.