Played by: Siobhan Finneran (pictured) and Rob James-Collier Where we left off: O'Brien vigilantly tends to Cora during her flu scare (what better way to make up for causing a miscarriage?), while Thomas, fighting in France, gets himself intentionally injured to return to his post at Downton. Also, Thomas's black market scheme doesn't go very well. What to expect: The former besties are now major enemies, which leads to some unsettling consequences. And still lots of fervent smoking.
Carnival Film & Television Limited for Masterpiece