Saburo is a high school student good in sports, but not very good with his studies. One day, Saburo travels back in time and arrives in the Sengoku period of 1549. There, Saburo meets Nobunaga Oda who looks and sounds just like Saburo. Nobunaga Oda is the son of a warlord and magistrate of the lower Owari Province. Nobunaga Oda though is physically weak and he asks Saburo to take his place. Then, Saburo as Nobunaga Oda attempts to unify the country of Japan.
High school student Saya Toma (Erika Toda) lost her parents and younger brother in an airplane accident. Detective Akio Kondo (Yu Tokui) came and told her “your family has a high possibility that they were killed by people who have spec.” That was the first time she heard of “spec”. 6 years later, Saya Toma, who has never forgotten what the Detective said, decides to become a detective. She returns to Japan after receiving training by the FBI in the United States. Saya Toma is assigned to work unsolved cases in the Public Security Bureau. Meanwhile, because of Satoshi Chii’s (Yuu Shirota) scheme, Juichi Ninomae (Ryunosuke Kamiki) considers Saya Toma his parents’ enemy and tries to push her to the edge. Satoshi Chii’s scheme has also caused Saya Toma and Juichi Ninomae to forget that they are brother and sister. The siblings are headed to a life-staking fight. A girl named Maho Ueno (Umika Kawashima) becomes involved in their fight. To protect Maho Ueno, Saya Toma uses “spec”.
Noboru is a high school student who isn’t popular at all. He looks up to senior student Miyazaki who is one of the most popular guys at school. Miyazaki has two girlfriends: Momose and Tetsuko. Momose and Tetsuko have totally different personalities. Momose is bright and Tetsuko is a popular student from a wealthy family. One day, Miyazaki is caught with Momose. To keep his relationship with Tetsuko, Miyazaki asks Noboru and Momose to pretend they are dating. They both agree due to their affections for Miyazaki. Noboru and Momose begin to act like a couple in front others and soon Noboru begins to develop feelings for Momose, who is still in love with Miyazaki.
Freelance writer Aoi Teshigahara (Miho Nakayama) lives in Paris, France. Sen Yagami (Osamu Mukai) is a photographer who came to Paris, France due to his younger sister Suzume’s (Mirei Kiritani) insistance. Over the next 3 days, Aoi Teshigahara and Sen Yagami fall in love. Meanwhile, Suzume meets her boyfriend Kango (Gou Ayano), whom they have been in a long distance relationship.
Tsugumi Dozono (Nana Eikura) works at a large electronics company in Tokyo. She likes to spend long vacations at her grandmother’s house in the countryside. One day, her grandmother passes away and Tsugumi Dozono decides to live in her grandmother’s house while working from home. She finds a strange middle-aged man in the house. The man’s name is Jun Kaieda (Etsushi Toyokawa). Jun Kaieda tells Tsugumi that he is her grandmother’s ex-student and her grandmother gave him a key to the annex house. Tsugumi, who does not know the exact relationship between her grandmother and Jun, begins to live with him.