Alex is watching his wife as she stands at the pale stone bench and raises her canister of Chinese herbal tonic to her shoulder to give it a quick shake. She gives him a game, faintly ironic smile, like someone pretending to be a cocktail waitress.

What's in there tastes nothing like a cocktail, Alex knows, because she made him try it the first day. More like lint from the vacuum cleaner, he thought at the time as he struggled to keep it down, blended with something indescribably bitter infused out of the boiled-up leaves and twigs and bits of bark in there. The day of their appointment he'd watched the Chinese herbalist grab small handfuls of this and that out of a wall full of drawers, seemingly at random, the whole place – the clinic, if you could call it that – smelling like anise and liquorice, mushrooms and exotic wood shavings.

He'd struggled to contain his scepticism as the guy had wrapped it all up neatly in white paper and handed it over to Mel, calmly naming a figure at the cash register that Alex thought at first he must have misheard. But Mel had removed her credit card, and handed it over willingly – eagerly, almost, like she was on the right track now and this was the price to be paid. Back at home she'd simmered the mixture exactly as directed in the special pre-purchased ceramic crock and made Alex take a sip.