This episode was filmed twice. The first time, it was filmed with regular contestants. Then, after the filming was done, some technical failure was discovered that for one reason or another rendered the footage unusable. The game could not be repeated with the same contestants, as they had already won their prize and they already knew where each of the prizes was hiding, so it was decided to bring back contestants from previous seasons to do a second filming of the whole episode. This second filming is the one that was finally broadcast, and only still photographs from the first recording have survived. One of the couples that was brought back were brothers Achutegui-Cerezo, who had been contestants in 1983, in season 3, and this eventually resulted in their never beaten record of permanence of 16 consecutive weeks as champions, more than a half of the whole season.