Reisuke Houjou's Plan to Attack Yukiteru's House is the third chapter featured in the Future Diary: Mosaic spin-off manga.
Minene is first shown visiting a shadow doctor, a doctor who takes care of criminals who are unable to visit a normal doctor. They are discussing the child which also happens to be visiting the same shadow doctor as Minene. His parents were killed under the "Omekata incident".
Minene goes out only a few seconds after to check on the kid, which is actually Reisuke Houjou, the 5th Diary Holder. He is taken by Minene in trying to take a bottle of potassium cyanide off a shelf. He falls down when Minene is trying to take him away, and it is here Minene finds a very abnormal list of his. Normally, 5th quickly takes the bottle and his list away from her. After quite a discussion between her and 5th, he decides to run away, crying. Minene goes after him and manages to find out that he would go to the Chrome Plating Factory to search after some hydrocyanicacid. 5th is soon shown on a bicycle at the factory, however he did not have to search long, after he manages to find both the hydrocyanicacid and his dolls at the same place. Of course, Minene sat a trap there, however 5th only decided to take the hydrocyanicacid and therefore the trap was not released, because of the reason that Minene placed them at the dolls. At the same time in the Sakurami Police Department there have been received a word that the factory that Minene happened to be in had been held up (obviously by Minene), and Nishijima is quick to suspect her after the details has revealed that the person had an eyepatch.
Later, 5th is placed in the Self Defense Shop in the Sakurami Shopping District. The storekeeper, Yoshi Gorou, is extremely surprised to see a child visiting her shop, and her surprise strengthens when 5th is asking after a stun gun and a gas mask. However, only one page after 5th is seen actually been giving the things he asked for, however right under the disk where the storekeeper happens to be at, Minene is kneeling down, pointing a gun at Yoshi. Soon Yoshi starts showing a couple of dolls to 5th, which obviously happens to be those of his own. However, 5th refuses to take his dolls back once again.
What seems like only a couple of minutes later, the police is shown inspecting the several places Minene and 5th has happened to visit during this chapter. More reports are being given to them, all at places where Minene (or "Minene look-a-like", as they described it) has been seen, and this is all simply caused by the reason that Minene would give 5th his dolls.
Thousands of police cars are placed just behind Minene, however she quickly absconds to a bank which she found out that 5th would rob later. As she sees 5th, she offers her a bag which was filled with the money of the bank that was planned to be robbed and, of course, also his dolls. And yet, 5th refuses another time.
Minene plans yet another time to give back his dolls, however she is unable to find the location of where he is going next, as the next thing as listed on his list only includes the word "pha". 5th is soon shown at the place where the dead bodies of his parents are placed. He decided to lay down in the middle of his parents' bodies, because he never got the chance to sleep side by side by his parents when they were alive.
After some time, Minene manages to find him at the place around his parents, and she finally gives the dolls to him and leave.