‘I propose that Catharina’s companion stole the gown, and the book and earrings, too, sometime in the winter of 1652, and that’s why she was let go. Her crime was discovered, but for whatever reason the goods weren’t reclaimed. Instead of selling them, she held onto them and packed them in her belongings when she took up her new role as companion to Maarten Horst’s wife. She probably intended to sell them later when she reached her new home in Sumatra. Your investigations into Catharina’s lack of personal connections with Texel support the theory, so it’s what I’ll be telling the press. I’ve already informed the vice-chancellor of the Glasgow School of Art and the Noord-Holland government. And I’m planning to contact Peta Humphries at The Guardian while you email your editorial contact at The New Yorker. Maybe we can instigate some kind of pitching war between the two of them. Imagine it.’

‘Hang on,’ I said, raising my palm. ‘Don’t you think that’s jumping the gun? We agreed to wait. I haven’t finished following up all my leads yet. Just because there wasn’t anything to connect Catharina to the island doesn’t mean the dress didn’t belong to Anna Tesseltje. I went digging into Catharina’s oeuvre. Her paintings are scattered in galleries all over Europe, but the Rijksmuseum is hosting some of her less-famous artworks as part of an exhibition on 17th-century art dealers called “The Birth of the Art Market”. There’s a painting there I’d like to see – it’s unfinished, but there’s a suggestion Catharina’s companion may have sat for it. The exhibition doesn’t open for another few weeks so I’m hoping I can convince the curator to let me take a peek. Her name’s Jeanette Hall; she was one of the senior art historians at the Courtauld gallery before she went freelance. I’m meeting her later this afternoon. I’m going to ask her if she thinks Anna might have borrowed the dress for the portrait sitting and forgotten to return it, or whether it’s possible Catharina might have given it to her as a parting gift when she left the household. Either theory could work.’

Liam looked sceptical. Leaning back against the metal workbench, he folded his arms.

‘You think so? You told me the companion was a laundress before she joined the van Shurmans. She was probably living in some rat-infested attic in one of the poorer districts in Amsterdam. If the dress was hers to begin with, why didn’t she sell it? A dress like that would have been worth a lot, even back then. She could have lived on the proceeds for a year. Come on, Jo. Listen to your instincts. What are they telling you?’