A unique deal between insurers and art lovers lay behind the triumphant return to public display last week of two masterpieces by British painter JMW Turner.

The Tate gambled £8m on buying title to Shade and Darkness - the Evening of the Deluge and its companion picture, Light and Colour - the Morning After the Deluge after insurers led by Hiscox paid out £24m after their theft in 1994.

Former fine art underwriter Robert Read of Hiscox said a deal was agreed under which title was sold to the Tate, despite the fact that the paintings were still missing.

Read said the hardest part was valuing the paintings while not knowing what condition they would be in if they were recovered.

In the event, they were recovered with no damage after eight years and were rehung last week.