亀は意外と速く泳ぐ

海外に単身赴任中の夫の言いつけを守り、彼の大切なペットである亀にエサを与えながら単調で平凡な毎日を送る若妻の片倉スズメ。そんな彼女とは対照的に自由な生き方をしている親友クジャクの姿に刺激を受けたスズメは、ある日、坂道で転げ落ちた拍子に偶然発見した“スパイ募集中！”の張り紙広告に思い切って応募。実は某国のスパイだと名乗る、どこか妖しげなクギタニ夫妻に雇われるが、結局生活は今までと大きく変わらず……。

Suzume Katagura (Juri Ueno) is an ordinary housewife whose spouse is sent overseas on business. She keeps regular contact by phone, but is more concerned with the welfare of his pet turtle, Taro. She dreams of being able to escape from her mundane existence one day. On one occasion, she accidentally floods her apartment, causing her to send in a plumber. Her best friend, Kujaku Ogitani (Yū Aoi) leads a much more interesting life than her and still wants more, namely a husband in Paris with a house with a view of the Eiffel Tower. Later on, while she is on some steep steps, a cart filled with apples accidentally unloads, prompting her to duck, and notice a tiny flyer advertising for spies wanted. After trying (and failing) to make her life more interesting, she replies to the advert and goes into a ramshackle home to meet the spy masters, unemployed couple Shizuo Kugitani (Ryō Iwamatsu) and Etsuko Kugitani (Eri Fuse), who work for an organization that is never referred to by name. They instruct her that her job is to remain completely boring and ordinary. She has this re-iterated to her when she buys a pair of sunglasses to make herself feel more like a spy. At one point, Suzume meets Kujaku in line for a chance to spin a wheel and win marvelous prizes (including a trip to France, hence Kujaku's excitement). While they miss out on a trip to France, they do win a fishing trip, which Suzume is more excited about than Kujaku. Suzume explains that she can never say "no" to Kujaku, because, when they were young, Kujaku cut off the power in the village so that Suzume could see her childhood sweetheart, Kato, in his pajamas, electrocuting herself in the process. The fishing trip is cut short when a body is discovered in the water. An unnamed group takes notice of the fact that the corpse did not belong to a Japanese, and was probably a spy, which starts an investigation to look for more spies. Meanwhile, Suzume meets Kato only to discover, to her horror, that he is bald. Wh