Sal Cinquemani of Slant Magazine complimented the album's consistency, but felt that "Hesketh's shrewd choice of collaborators is often squandered on rather rudimentary song structures and lyrical ideas. That doesn't make Nocturnes any less enjoyable of a dance-pop album, but it's ultimately what will keep Little Boots from becoming the next Madonna , or the next Robyn for that matter."  In a mixed review, Katherine St. Asaph of Pitchfork Media noted that " Nocturnes finds [Little Boots] settling on one that aspires to the distance of Saint Etienne 's Sarah Cracknell or Sophie Ellis-Bextor . She's not quite there, and when her approach doesn't work, it really doesn't". Nevertheless, St. Asaph viewed the album as "a big improvement over Hands , [...] where even the biggest singles' hooks were made of saccharine, not sugar."  Consequence of Sound 's Dan Pfleegor opined that "[t]he trouble with Little Boots' choice in house music is that there's little room for experimentation. At times, lyrics rhyme just to be adhesive and the beats drone on and on and on", while concluding that "Little Boots can always be counted on to do what she does best though: keep us moving, keep us feeling, and, of course, keep us dancing."  Clash ' s Jack Scourfield expressed, "For the most part, [...] Nocturnes feels a bit tired—'Broken Record' [...] even apes her own past hit ' Stuck On Repeat ' lyrics-wise. But the results here feel somewhat less spirited."  Despite writing that the album "features some catchy and classy electronic dance music ", Kurt Murphy of the NME critiqued that "'Broken Record' sounds like a Eurovision -endorsed soundtrack to Cassack [ sic ] dancing and 'Satellites' is a limp version of Madonna's ' Ray of Light '." 
The strain of living under these conditions caused Heda to become critically ill, but she was initially denied medical treatment. When she was finally admitted to hospital she had a temperature of 104 and a long list of ailments, leading the doctor who treated her to compare her to a newly released concentration camp survivor. It was while she was recovering in hospital that she heard Rudolf’s trial testimony broadcast on the radio, and she listened to her husband monotonously admit to ‘lie after lie’ as he recited the script he had been forced to learn. Forcibly discharged from hospital before she was fully recovered, Heda was so weak that she had to crawl ‘inch by inch’ from the front door of her apartment block to her bedroom, where she spent several weeks following Rudolf’s execution ‘motionless, without a thought, without pain, in total emptiness … lying in my bed as if it were a coffin’.