Rope in the Skylight

Cases unlock in order, like levels. This is case 199 of 200.
Feltham, Monday, 30 January 2017, 9 am. In a customs cargo warehouse near Heathrow, the night guard found two round holes in the skylight at 6:15 am and a cut rope hanging from the ceiling.
Below, in bay 4, three booksellers' trunks stood open and empty. More than 200 rare books were gone: astronomy treatises, atlases and prints, valued at £2.5 million.
The trunks were meant to be in the high-value cage, where the expensive cargo is kept. The floor motion sensors never triggered, and nothing else was taken.
The books were due to fly out at 8 am for a fair in California. Three people knew where they were. One of them knows where they are now.
Cargo warehouse near an airport in 2017, with empty trunks and a cut rope hanging from a skylight.
Suspects
Royston HargreaveNight guard of the warehouse, 61 years old
Callum BrierleyDay-shift supervisor of the warehouse, former industrial climber, 39 years old
Graziella ToscaniRepresentative of a Turin bookseller, who escorted the trunks to London, 54 years old
The real case
The Feltham rare book heist
London, United Kingdom, 2017
Read the real case