On holiday in Menorca, Nick worries about Charlie, who is struggling more than ever. Isaac starts to feel like a third wheel around Elle and Tao.

It’s a tough Christmas for Charlie, and his family — except for Tori — isn’t helping. Elle and Tao talk about sex, and sparks fly at a New Year’s party.

With the Martian invasion gathering pace, George and Amy each face their own terrifying ordeals. Desperate to be reunited, a lifeline comes to them at the beach.