BBC:
"So what they decided they would do was to put each of the heads into white buckets that you could seal," she said.
"And so we didn't disturb anyone at the airport, I would carry them in two very expensive designer carrier bags so that it didn't look obvious."
Prof Black was given two letters, in English and Italian, explaining what she was carrying.
...
Prof Black said a security guard at Heathrow Airport then said the bags needed to be opened, so she gave him a detailed description of what he might find inside.