For six months, suspicions swirled.
The five missing Hong Kong booksellers, many speculated, were most likely spirited away by mainland agents. Even more chilling was the notion that one of them was likely seized from within Hong Kong. But there was little to confirm the public's fears. The booksellers "confessed" on mainland television to their crimes and, on their return to Hong Kong, said they had nothing to add.
Mr Lam Wing Kee broke that spell.
Two weeks ago, he met a room full of journalists, and the "truth" came spooling out.
He was taken by a "central special investigative unit" in Shenzhen, blindfolded and transported to Ningbo. He was detained for nearly eight months with no access to a lawyer or family. The confessions were scripted. Another bookseller, Mr Lee Bo, told him he was taken out of Hong Kong against his will.
Even though Mr Lam's claims cannot be verified, most Hong Kongers believe in the gist of his tale. It confirmed for them that Beijing's long arm will stretch across the border in extrajudicial rendition, never mind the "one country, two systems" framework. It will even reach into Pattaya, Thailand, where a third bookseller, Mr Gui Minhai, was apparently taken. It did not matter that Mr Gui is a Swedish citizen.
All this exacerbates the city's distrust of the central government.
Beijing made a somewhat conciliatory gesture on Monday, saying it will discuss a review of the existing notification mechanism, which needs "improving". The security authorities are supposed to inform the other side within 24 hours when they detain residents from the other side of the border.
It may be a token gesture, but it does indicate recognition by Beijing of the extent to which the episode has perturbed Hong Kong, and the need for some form of damage control.