One night, Mrs Mitsuba circles the eleventh of an unknown month - it's her birthday tomorrow! Hoping for some birthday pampering, she goes to bed.
Next morning, Hattori meditates on the roof, when he sees Mrs Mitsuba walking out of the gate. Wondering what she's up to so early in the morning, he continues with his meditation.
Mr Mitsuba and Kenichi quiz each other where Mrs Mitsuba has got to. Meanwhile in town, Mrs Mitsuba sits in a hairdresser's chair, her hair done up in curlers. As she comes home, she asks the family if she looks different. They all reply negatively, and Mrs Mitsuba snaps.
Later on, Hattori trains himself at shuriken-throwing while Kenichi, Shinzo and Shishimaru watch on in amazement. Shinzo has a go - but loses his grip and falls on top of Shishimaru, but with good reason as Shishimaru served as a trampoline for him. As Shinzo has another go, Mrs Mitsuba calls the boys in for lunch. She is disheartened as Kenichi is more focused on his television than the food, but Hattori and Shishimaru epnjoy themselves.
That evening, as Hattori and Shinzo train and Mr Mitsuba plays golf, Mrs Mitsuba turns up dressed in a stunning outfit. She tells them that she's taking them out for dinner before asking them what day it is. Mr Mitsuba has first say and says that it's the launch of a new TV programme, Kenichi says that it's the launch of a new comic, Shinzo says that it's celebrations for his ninja skill improvement, and Shishimaru says... chocolate rolls day, of course. Mrs Mitsuba, apparently furious, flies off the handle at them before storming back into the house. As they suddenly remember, they beg her for forgiveness, but she unfairly dismisses them, saying it's too little too late. Kenichi pleads Hattori to do something. Hattori sends a bird into the house to talk to Mrs Mitsuba, and it tells her that despite her beauty, she has a very short temper. Mrs Mitsuba cracks, and the bird flies off.
After that, Mr Mitsuba paints a large banner - only to be shouted at by Mrs Mitsuba for being messy and getting paint over himself. How rude! In another botched attempt to cheer their matriarch up, Kenichi picks a bouquet of roses from the bush, but Mrs Mitsuba throws him out when she finds that he picked them up from the rose bush she had been taking care of. If criticising Mr Mitsubas messiness is rude, this is worse - it's the thought that counts!
As the family sit in despair, Kanzo suggests they cook something special for a birthday meal. As Shinzo and Shishimaru decorate the living room, Hattori, Kenichi and Mr Mitsuba work in the kitchen. As Mr Mitsuba gets ready to make some chicken and Kenichi some bullseyes, Hattori prepares to bake a cake. Unfortunately, the cluttered cupboard bursts open and all the contents fall on poor Kenichi, and Hattori drops the flour. Mrs Mitsuba hears the rumpus and crawls out of the abandoned master bedroom.
Meanwhile, Mr Mitsuba and Hattori haul out a semi-conscious Kenichi and revive him. Just then, Hattori smells something burning and realises the ugly truth - the chicken has caught fire! Shinzo and Shishimaru hop into the room and see the kitchen in a clutter. Hattori suggests they just have a party. As Mrs Mitsuba comes to her senses and realises that family is more important than expensive gifts, she walks out into the living room - and sees how much her family care for her as she looks at the decorations. They blow the candles out together and tuck in - but the food is revolting! Thankfully, Mrs Mitsuba remains stoic, knowing that more problems will arise if she loses it again. Hattori is relieved.
Yumeko Kawai (mentioned)