Episode 3 rounds out our stint on "Back to the Future" with a lengthy discussion of mess of "Part III" timelines, Marty McFly's personal growth, and what the hell a "BttF: Part IV" would look like ("Revenge of the Martys," probably).

-Last time, on Paradox: Doc Brown has yet more information about the future
-In fact, Doc Brown is super-bad about this whole "don't meddle with time" philosophy
-The timeline becomes a mess
-Professional Teenager Marty McFly
-Pie-tin Frisbee
-How badly should Hill Valley be altered by all this
-What the hell was Doc up to with all that extra time?
-The shape of a BttF quadquel