There’s a particular type of hangover – where glumness and ennui hang heavy over me – that can only be cured by laughter. When a reminder is needed that things can be all right again, I reach for my phone and trawl through the reviews of a small operation near South Kensington tube station: Janet’s Bar.

The majority of the reviews rate Janet’s as ‘one-star’ or ‘terrible’ according to TripAdvisor’s taxonomy. Nume­rous posters lament the absence of a zero-star rating. The titles of the reviews themselves tell their own story:

‘Atrocity exhibition ‘

‘I need a shower’

‘Abomination’

‘Avoid like a horrible disease’

Janet, who is not an abstract or invented mascot but the owner herself, features heavily:

‘Janet is the worst person I have ever met’