Jennifer Love Hewitt (Maddie Buckley Kendall) and Brian Hallisay (Doug Kendall) are married in real life with three kids. They also previously starred as husband and wife in the show The Client List (2011).
Oliver Stark was considering quitting acting and becoming a firefighter before getting cast as one on 9-1-1 (2018).
One episode begins with a wedding party that ended in a catastrophic building collapse where the floor gave out under the weight of all of the party goers (Point of Origin (2018)). This is based on an actual event that occurred in Israel where 24 people lost their lives as a result of a floor giving out due to poor or improper building materials used during construction.
In firefighting lingo, Alpha, Bravo, Charlie, Delta, are terms are used to designate the sides of a structure.
- "Alpha" refers to the front side of the structure
- "Bravo" refers to the left side of the structure,
- "Charlie" refers to the back side of the structure
- "Delta" refers to the right side of the structure
After two episodes aired, Fox renewed 9-1-1 (2018) for a second season, announced on January 16, 2018.