A recurrent song throughout this episode is "I Love To Love (But My Baby Loves To Dance)," by British disco artist Tina Charles (circa 1976).
In the opening scene in the car, John (Stellan Skarsgård) and Stevie (Nicola Walker) are counting Weight Watcher points for wine and fast food.
The poems quoted are from "Romeo and Juliet" by William Shakespeare.
The poem which starts "Heaven is here ... is from Act 3 Scene 3 and the one which begins "Here, here will I remain ...." is from Act 5, scene 3.
Nicola Walker (Jackie 'Stevie' Stevenson), Adeel Akhtar (Ira King) and Josef Altin (Christopher Riley) also worked together in Unforgotten (2015), as DCI Cassie Stuart, Hassan Mahmoud and Tyler respectively.