ET exclusively debuts a first look from Monday's return episode.
9-1-1 returns for its spring premiere and it's back to work for the 118.
On Monday's episode, titled "Outside Looking In," an extravagant birthday celebration goes sideways when the girl at the center of the party -- dressed in a fire-engine red gown being flown high in the sky by dozens of white balloons -- accidentally comes across a body when the plastic tarp on the roof of a neighboring home unexpectedly comes off with a strong gust of wind.
The 9-1-1 call comes in and immediately Bobby, Hen and the team race to the scene to see what they can do to help. Though the girl's birthday party is seemingly ruined as fire trucks and ambulances litter the street, she's ecstatic about the turn of events as she records the action on the scene.
But as they get to work, Hen and newbie Jonah (guest star Brad Durfee) have a little spat as he tries to correct her when she calls him "Monday," a nickname she gave him because there's "a new one of you every day."
Watch ET's exclusive sneak peek below.
9-1-1 airs Mondays at 8 p.m. ET/PT on Fox.
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