(Some months earlier, two brothers are seen smirking as they stand in front of a defeated young girl.)

Munechi: This is for breaking my chin!

(He kicks the girl down as his brother grabs her.)

Toshiji: Now where's your friend?

(Out of a sudden, two figures show up and kick the brothers away.)

Munechi: (glares) You...

(The figures are revealed to be Rinko Akiyama and Ken Hunter.)

Rinko: Yukikaze, are you alright?

Yukikaze: Took you both long enough...

Ken: (to Rinko) Take Yukikaze away, Rinko. I'll take care of these fatties.

Yukikaze: (gets up) Don't you dare to die, got it?

Ken: (in mind) Tch, flat chested tsundere...

Rinko: (helps Yukikaze up) Let's just go already!

(Then Rinko takes Yukikaze to safety while Ken pulls out his Shinobi Hyoutan.)

(He then uncorks the Hyoutan, and pours its content onto his waist as he prepares to transform.)

Ken: Henshin!

(He places his Menkyo Kaiden Plate into his driver and spins its shuriken.)

DARE JA? ORE JA? NINJA! SHINOBI KENZAN!

(Ken becomes Kamen Rider Shinobi.)

Shinobi: Writing the way of Shinobi with the blade of my heart! Kamen Rider... Shinobi!

(Shinobi dashes at the Yasaki Brothers while dodging their punches before kicking them away.)

NINPO KIRISUTE!

(Shinobi Summons a Ninjatō from the back of his belt, and slashes both of them.)

STRONG NINPO!

(He fires a stream of purple flame from his hand, bringing the Yasaki Brothers down.)

MEGATON NINPO!

(He then summons a giant tornado to lift them mid-air. And as they fall down, Shinobi prepares to finish them.)

FINISH NINPO!

(Shinobi attacks the Yazaki Brothers in high-speed movements while shrouded in a purple aura as he does a combination of punches before doing a spinning kick, finishing them as they explode.)

Shinobi: That takes care of the problem.

(Shinobi reverts back to Ken as he returns to Rinko and Yukikaze.)

Rinko: Welcome back, love.

Yukikaze: Glad you're still alive!

Ken: I wouldn't call me "baka" if I were you!

Yukikaze: But THAT'S what you are! You know why? Because you're OUR baka, baka!

Ken: (in mind) Once a tsundere, always a tsundere...

(What Ken doesn't know is that will soon meet other Kamen Riders like him.)