The Ninja

Plot: Its 12.00 at night and Phineas and Ferb here a scream. Its coming from Isabellas house. They suspect a ninja is behind this meanwhile Dr Doofinsmirtz is stealing chocolate. The next day a girl named Pearl Falls notices Phineas and Ferb and has a crush on Phineas which angers Isabella. Ferb is suspicious of Pearl and her innocence thinking that she is The Ninja. Phineas thinks that Ferb is joking then Pearl asks to help them build something which angers Isabella straight to the point to insanity the thing there building is a UltraHelmet. They test it resulting in the helmet stuck to Phineas. Phineas and Pearl spend time talking to each other which make Ferb and Isabella jealous. Ferb goes to Pearls house and sees a shrine to Phineas and a secret door. Ferb goes to the door and finds a ninja mask a nunchuck and ninja clothes. He rushes to Phineas and tries to warn him that Pearl is The Ninja but Phineas tells him that there on the lookout for "him" At night they see The Ninja and try to follow "him"  but