Mnemonic symbol: the artist Ai Weiwei. Shortly after finishing a new installation in the Eiffel Tower's bathroom (ei4), Ai Weiwei (未) is imprisoned by Willy Walrus (w), because—out of all places—Ai Weiwei put his new installation right into Willy Walrus's toilet. Ai Weiwei's installation is a Christmas tree (木) with a tiny, slightly tilted flute (一) on top. Ai Weiwei would really, really like to correct the tilted flute, but so far, Willy Walrus has not yet (未) let him out.