Another dead end. With Vidor continuing to stonewall, short of strapping his patient down and threatening him with shock therapy, what could Gessen do? But each time he suggested there might have been friction between father and son, Vidor countered with another saccharine tale of paternal heroism, and how the man had surely taken his rightful place in the pantheon, alongside the other gods.

Gessen paged through his notes. Could the trauma have originated from someone else? Another family member, a neighbour, a friend. Or was he simply grasping at straws, and there was truly nothing to uncover? A case of Gessen’s own traumatic history colouring his judgement.

When Mathilde came into the room with his coffee and the day’s mail, he leapt up to take the tray, welcoming the distraction.

‘Shall I light the fire in the sitting room?’ she asked. ‘It’s chilly today.’

The thermometer outside the window hovered just above zero. Chilly indeed. ‘Thank you, Mathilde. If it’s not too much trouble.’

‘Not in the least, and it will do you good to sit by the fire. If you don’t mind my saying, you look terribly worn out. When was the last time you took a proper holiday?’

He smiled. She knew the answer as well as he did. ‘Two years ago?’

‘More like seven.’ She lingered in the doorway, her usually brisk expression softening. ‘If you’re not careful, you’ll end up on the other side of that desk.’

She might be right. Yesterday, he’d been overwhelmed by desire to run away, to escape his fractious patients and gnawing worry about the fate of the clinic. It was true he hadn’t had a holiday in ages, and he sometimes dreamed of sprouting wings and flying over the Alps to the warmer climes of Italy.

Years ago, not long after finishing his studies at the Sorbonne, he’d read a newspaper article about the plight of the swallows in Switzerland, too exhausted and hungry to make their migratory flight to the other side of the Alps. The weather so harsh that the exhausted birds were being gathered up in cages and flown in aeroplanes to their winter feeding grounds in sunny Ticino. The favourite bird of his first and only love, and the clinic’s namesake. At the time he’d wondered, with a pang of sadness, if Sophie might have read the same article, and imagining her gratitude at the quirky generosity of the Swiss. Transporting the birds over the very mountains he could see outside his window, because they were unable to make the journey on their own.

He met Mathilde’s questioning glance and suppressed his habitual response. It was their old argument. Though a good ten years his junior, she’d been his faithful aide-de-camp for many years, and her maternal chiding was woven into their dynamic. ‘By the way,’ he hesitated, ‘has Ursula said anything to you?’

‘What about?’ Her look was inscrutable.