Thomas Penn

 was involved in a legal dispute with Benjamin Franklin over taxes and proprietary claims in the colonies.

In 1762, he lived on 10 New Street, Spring Gardens in London. Abigail Holt was seen entering his house. (AUDIO: The Founding Fathers)

Behind the scenes

 * The nature of the dispute is only hinted at in the story. In real universe, it was related to the state of Pennsylvania, which was a given to Thomas Penn's father by King Charles II in lieu of a debt payment and still bears the Penns' name. Franklin petitioned the king to replace the Penn proprietary government with a royal government.
 * The address of Thomas Penn's house in the real universe was the same as in the DWU.