Superman II: The Richard Donner Cut

(at around 16 mins) The actor playing Clark Kent yelling out to Lois Lane after she jumps out of the Daily Planet is not Christopher Reeve. An uncredited actor was brought in to film the shot for the DVD release.

Superman turns back time so that General Zod, Ursa and Non never leave the Phantom Zone, but we aren't shown how Superman deals with the missiles launched at the end of the first Superman movie - meaning, after turning back time, they should escape again, if Superman dealt with the nuclear missiles in the same manner. (This is a problem that actually stems from the first movie, where we aren't shown Superman dealing with the crisis in a different fashion after Lois dies - he shows up at Lois' car, and the aftershocks that caused her death just never happen.)

The next scene we see is meant to be the beginning of the movie again, with the Daily Planet - so after the nuclear explosions, and before the arrival of the villains - but Clark goes back to straighten out the trucker who hit him afterwards - though because Superman turned back time, basically, this event never happened - so Clark was hitting an innocent man for no reason. (The diner owner says that he just had the place fixed up - meaning the scuffle did occur, and Clark claims he's been working out, meaning from the last time they saw him, when he was beaten - however, again, this never happened because Superman turned back time again.)

Moreover, towards the end of the film, Superman destroys the Fortress of Solitude with his heat-sight - the Fortress of Solitude should be reconstructed (and with Jor-El available to guide Kal-El again) due to Superman turning back time again. The time travel device, beyond complicating the film's time-line, nullifies Jor-El's sacrifice and Superman's lesson, as after turning back time, things should be "back to normal" again.

Furthermore, if Superman's end-game was to turn back time all along, he didn't have to fight the super-villains in Metropolis or in the Fortress of Solitude at all - he could have turned back time immediately after regaining his powers, or following the Metropolis fight.

After the Warner Bros./DC Comics logos, there is an on-screen dedication "in loving memory" of Christopher Reeve, "Without whom we would have never believed a man could fly".

Edited from Superman II (1980)