one day:

Isabella: hey phineas whatcha doin?

phineas: I'll explain in a moment but first take this gum that lets you breathe underwater permanently and turns you into a fish when the plot dictates it.

Isabella does so

Isabella: ok now what's going on?

phineas: we're going to the underwater world of finding nemo and i don't wanna have you almost drown like what happened when you and melody were chucked by morgana into her underwater ice cave

They warp at the drop off

Isabella: what kind of fish did i turn into, phineas?

phineas: you're a rainbow fish and I'm i don't know a mackerel or something

Isabella (notices the scene of the diver about to capture Nemo as well )

Isabella: I've gotta save him

(diver catches both her and Nemo in the bag)

Isabella: i didn't think this through! phineas! save me!

phineas: Isabella! no!

marlin: I've gotta chase that boat that took him

phineas: it also took my friend I'll come with you

on the surface boat

(both are about to be put in his box thing)

Isabella: please free us

diver: woah hold on

(from here until the plots intertwine I'll be focusing on the Nemo, Isabella and tank gang part of the plot so next time will be when they're put in the tank