Viewers
According to Nielsen Media Research, the episode was seen by an estimated 2.24 million household viewers and gained a 0.6 rating share among adults aged 18–49. This means that 0.6 percent of all households with televisions watched the episode.[1] This was a 9% increase over the previous episode, which was watched by 2.05 million viewers and had a 0.6 ratings share.[2] With these ratings, Brooklyn Nine-Nine was the third highest rated show on NBC for the night behind Superstore and Law & Order: Special Victims Unit, sixth on its timeslot and eighth for the night, behind Broke, a Young Sheldon rerun, Superstore, Law & Order: Special Victims Unit, Last Man Standing, Man with a Plan, and the 2020 NFL Draft.
Critical reviews
"Lights Out" received very positive reviews from critics. LaToya Ferguson of The A.V. Club gave the episode a "B" rating, writing, "'Lights Out' wasn't the best episode of this season, but it was able to take its predictable sitcom plots and prove that they can still work in a contemporary context, even if you continue to play them straight. Major credit goes to the cast for their delivery of this material but it also goes to Goor and Del Tredici for understanding what makes these plots work and the necessary beats for breathing some energetic life into them. And despite the simpleness of the plots themselves, this couldn't have been an easy episode to shoot because of the blackout and nighttime components of it all."[3]
Alan Sepinwall of Rolling Stone wrote, "Perhaps best of all, under these strange circumstances in which the episode airs, there’s no cliffhanger of any kind, not even a relatively low-stakes one like Holt’s demotion. With the world still mostly frozen, it’s unclear when TV shows will be allowed to resume production, let alone when the traditional broadcast network's 'midseason' will start. So it could be quite a while before we get to return to the Nine-Nine. With the series again finding a way to age oh-so-gracefully, that wait might feel very long. But 'Lights Out' offered the kind of warmth and silliness that feels right to pause on, until whenever the series, and life, can return to something resembling normalcy."[4] Nick Harley of Den of Geek gave it a 4.5 star rating out of 5 and wrote, "Brooklyn Nine-Nine wasn't always perfect this year, but it hit the mark more often than not. 'Lights Out' made the most of its supporting cast while relying on the leads to sell the emotional beats. It also featured Holt dancing to 'Push It' and honestly, what's better than that?"[5]