The one at the back

Cold tea ads show ice and blue light. But the choice happens in three seconds, one hand already on the fridge door, and nothing on TV reaches that moment.

Everyone knows the bottle at the back is colder, and everyone reaches past the front row for it. Nobody has ever said so.Everyone knows the bottle at the back is colder, and everyone reaches past the front row for it. Nobody has ever said so.Everyone knows the bottle at the back is colder, and everyone reaches past the front row for it. Nobody has ever said so.Everyone knows the bottle at the back is colder, and everyone reaches past the front row for it. Nobody has ever said so.

Clear anti-fog film on the outside of convenience-store doors, with the words cut out. When the door opens and shuts, the glass fogs everywhere except the film, and a line appears in the fog: “The one at the back is coldest.”

The ad only exists just after someone has used the door, and it fades on its own in about a minute. No screen, no print, nothing to take down but a sheet of film. Filming it is the obvious thing to do.

1. Fog doorsAnti-fog stencils on chiller doors in 300 stores. Words appear after the door is used.
2. Front row, back rowShelf-talkers that send you to the back of the row, where 3° is always restocked.
3. The posterThe same finger-written line, for places with no fridge door.

• Doors running, and fog-up time checked per store
• Share of the chiller against stores without film
• Unprompted posts filming the door
• Trial among people who name the line