The Ood stage a revolt against their slavers ("Planet of the Ood"), the Sontarans wage war for Earth ("The Sontaran Stratagem" / "The Poison Sky"), UNIT returns, The Doctor makes a political statement, Ian Chesterton flies a jetpack, and Mike's opens a tumblr. Also, there are spoilers for the second half of the seventh season between 7:23 and 12:47.