phineas and ferb episode "2nd dimension"

when i saw the episode about the 2nd dimension, in season 4 year 2014, i had not yet seen the "movie" about 2nd dimension from 2011.

to help bridge between the two stories, they gave a "narration" that was "reminiscnet" of the style in lord of rings "much that was, is lost" clever !! it reminded me of the similar phrase. and other stylistic references... however it was not clear enuf for me, to understand the idea of second dimension place in the series. only a reminder for those who had already seen the movie from 2011.

so i add here a more clear bridge for the episode, kuz its story is IN the second dimension.

i also ask? the "original" series must have been in the "second dimension" because it is "drawn" on paper which is 2-d so how can they go "from first dimension to second and return home"?

anyway... here is the bridge:

BRIDGE [to help those who did not see or did forgot the 2011 movie]

title: resistance, return 2nd dimension

the narrator, Charlene 2 [meaning in the 2nd dimension, the place of the following story], tells that the "great empire fell", because of a choo-choo [a reference to the story in P&F  "movie across 2nd dimension" (2011) when Dr. D gave D2 the toy train, the one D2 had lost causing D2's anger, ending his desire to rule and causing D2 to use the self destruct option for vaporizing his norm-robot army.]

d2 was imprisoned in 2nd dimension (not defeated) so: "In the 2nd Dimension, while Doofenshmirtz is in prison, Isabella's pet went missing. Also many animal agents of O.W.C.A. went missing. Phineas, Ferb, Candace and her resistance fighters must find and defeat this new foe.

Summary

The narrator (Charlene 2) told about a certain event when the "love of a choo-choo" caused the fall of an empire. (This refers to Dr. Doofenshmirtz giving his toy train to Heinz Doofenshmirtz of the 2nd Dimension, causing Dr. D2 to end his attack on the 1st Dimension, by pressing the self-destruct, to evaporate his Norm Bots.)

In the 2nd dimension, Dr. Doofenshmirtz is in prison for his many crimes. Two months after the new freedom, Candace, the leader of The Resistance woriess that evil will return to Danville.

In the Flynn-Fletcher backyard, Phineas, Ferb, Dr. Baljeet, and Buford are listing the summer activities that they have planned to do. Phineas says that they'll be having so much fun, since Perry returned to their family (after being changed to a cyborg). Now he plays with his pet by throwing a stick, and Perry uses his cyborg system to shoot the stick.

The gang sees a hidden bunker containing sports equipment etc. 

then the story is about the cyborg animals. how will the resistance led by candace defeat the cyborg-animal army? they will... but how?