Chen is stressed: he's overworked and sleep deprived as his obstetrician wife Ming monitors her fertility.

Fitz and Ming talk about their insemination plans. Chen pursues his dalliance with Sienna, a flirtatious resident.

Chen confronts Fitz with an old stash of his letters to Ming. Fitz denies there's anything between them.

Five years earlier, Ming suffered a miscarriage. Back in the present, Fitz goes to see Ming.

In a flashback to Christmas Eve three years earlier, the complicated and interlinked early relationships between Ming, Chen and Fitz come under the spotlight.

Fitz is sound asleep and hung over when he gets a call to go to the airport for an emergency transport.