As Elizabeth welcomes Britain's first woman prime minister and Charles meets a young Diana Spencer, an IRA attack brings tragedy to the royal family.

Margaret Thatcher visits Balmoral but has trouble fitting in with the royal family, while Charles finds himself torn between his heart and family duty.

While Margaret Thatcher struggles with the disappearance of her favorite child, Elizabeth reexamines her relationships with her four children.

As many nations condemn apartheid in South Africa, tension mounts between Thatcher and Elizabeth over their clashing opinions on applying sanctions.

Amid a growing challenge to her power, Thatcher fights for her position. Charles grows more determined to separate from Diana as their marriage unravels.