Whoever was responsible for the exhibition presentation must have realised that Mr Sin standing with his eyes closed looked a little peculiar, because later photos reveal that the dummy was modified to open up the eyes and pose the left arm wielding a knife. The re-worked display now featured part of the House of the Dragon set from Talons as a backdrop for Mr Sin.

Older exhibits were regularly discarded to make space for new ones, and also exchanged between the Blackpool and Longleat venues: by 1980 the head alone remained in a wall display of masks, draped in fake cobwebs. The details present in the high resolution version of this image confirm that the 2008 mask is the one displayed in the Doctor Who exhibitions between 1977 and 1980.

Although difficult to see on these photos, the dummy's "eyes open" effect was achieved by fitting translucent beads. These are the beads now present on the 2008 mask, and examining its interior demonstrates exactly how the eye modification was carried out.

The original rectangular eyelid panels (they are made of the same papier-mâché as the rest of the mask) were simply detached, moved up, then glued back on. Beads were threaded on to short pieces of string and glued in place across the open eyeholes. The white polystyrene headblock now showed through the eyeholes on either side of the beads, resulting in the eyes taking on a large and bright appearance quite at odds with the original look of the character. (I have now placed a strip of black paper behind the eyeholes to minimise this unwanted effect.)

So although now open, the 2008 mask's eyes were originally closed exactly like the dummy's, and the closed eyelids are still present on the mask - consequently the original eyelashes also survive, and it is possible to see that the lashes of the left eye retain the distinctive clustering visible in the TV episodes.

The accumulation of evidence was by now overwhelming; the 2008 mask is without doubt the original dummy prop used in The Talons of Weng-Chiang. However, for the sake of thoroughness, I still felt it was necessary to explore the possibility of a stand-by mask existing.