On Valentine's Day, a surprise marriage proposal goes awry with dangerous consequences. Athena attempts to help a desperate woman and unintentionally joins the Lonely Hearts Club. Bobby and Chimney pull holiday duty and learn about the "Casanova Fracture" and Abby and Buck go on their first official date.
- Angela Bassett as Officer Athena Grant
- Peter Krause as Captain Bobby Nash
- Connie Britton as 911 Operator Abby Clark
- Kenneth Choi as Firefighter Howie Han
- Aisha Hinds as Firefighter Henrietta Wilson
- Rockmond Dunbar as Michael Grant
- Oliver Stark as Firefighter Evan Buckley