Overview: Who are you? After sacrificing himself to save both worlds, Peter mysteriously returns to ours. But he has been forgotten - by Olivia, by Walter, by everyone. It's as if he never existed. At the same time, shapeshifters controlled by an unknown master begin an onslaught of destruction, and now the two former enemy universes must cooperate to defy a common foe.

DVD Verdict: As I hope you all know by now, 'Fringe' is a show is about an FBI Division that explores the freak or unusual phenomena. The relationships that have been born between Peter and Olivia, Astrid and Walter, and Peter and Walter are just so deep and wonderful to watch. Sure they get a little diluted here in season 4 due to Peter being lost between the two worlds as if he didn't ever exist, but that aside all the characters are still so rich and so interesting. I mean, come on now, Walter Bishop is just the best Mad Scientist since Doc Brown, is he not?! In the season opener, 'NEITHER HERE NOR THERE,' we open on Olivia facing down her Parallel Olivia, before we get down to the facts to support the season. Peter is still "gone," although he flickers in an out in the background unnoticed (for the most part), Lincoln Lee is now (basically) Olivia's "new" partner; and neither remembers either from the parallel universe, and its story is the ongoing arc - which is a new breed of bodysnatchers are operating in the real world, with technology from the parallel universe within them!

In the second episode, ONE NIGHT IN OCTOBER, a serial killer in the parallel universe is tapping into peoples brains and freezing them as they spill their happiest memories. In the next episode, 'ALONE IN THE WORLD' Walter is still having the halucinations of Peter (although he has no idea who he is), and a creeping killer is, well, creeping its way into people and decomping them within mnutes. In 'SUBJECT 9,' an astral projection is haunting Olivia, but is it friend or foe? Also, Peter finally comes back to Earth as a human - and yet nobody knows him!

In 'NOVATION,' the bodysnatchers are back, and so too is Peter - trying to convince everyone they do know him and that he can help them with the bodysnatchers. In 'AND THOSE WE LEFT BEHIND,' for me the best episode of the season, time moves / dej vu is being experienced by everyone. Caused by a devoted husband (Stephen Root from 'Newsradio') for his wife, it also includes a great Styx headphones moment in the lab! In 'WALLFLOWER,' an invisible man is killing people for their pigment, but is he linked to the Massive Dynamic program from days gone by? Also, the reason for Olivia's constant headaches is revealed.

In 'BACK TO WHERE YOU'VE NEVER BEEN,' Peter begs Walter to help him get the machine operational again to get hime back to his own time line. In 'ENEMY OF MY ENEMY,' more body doubles are out and about, and now within the HQ in the alternate universe. Also, the Puppetmaster is revealed and he is an old foe. In 'FALSE PROSPECTIVE,' a teenage girl has premonitions about people dying, and can draw quick pictures to show them. But, is there another link to Massive Dynamic's past.

In 'MAKING ANGELS,' Astrid comes over from the alternate universe to check out the lab and everyone within it. Also, a poison is being introduced to people with ailments by someone who can see their future. In 'WELCOME TO WESTFIELD,' a magnetic force brings down a plane, shuts down cars, and traps the team in a small town. In 'A BETTER HUMAN BEING,' a young man in a mental institution hears voices in his head, and seems to be in on their killing spree too - all from his bed! Olivia starts to recall memories of Peter's other time line Olivia and a BIG reveal is, well, revealed come the end!

In 'THE END OF ALL THINGS,' Olivia is kidnapped and the old foe puts his plan into action. In 'A SHORT STORY ABOUT LOVE,' Olivia's back, but recently widowed women are being targeted by their dead husbands pheromones. The Observer leaves a clue behind for Peter and this episode wraps with a lovely moment. In 'NOTHING AS IT SEEMS,' an old beast is brought back to the series to cause some damage and Olivia is still having the other time line Olivia's memories infiltrate her mind.

In 'EVERYTHING IN IT'S RIGHT PLACE,' Agent Lee goes over into the alternate universe to help with a case. One that includes a shape shifter. But, sadly, one of the main cast dies! In 'THE CONSULTANT,' a plane crash and a taxi accident - with fatalities for both sets of the people at the same time - is just the beginning of the old foe's horrible game plan. In 'LETTERS OF TRANSIT,' it's a major flashforward to 2036; a time moved on from 2015, when the Observers took over the world and those humans that survived an uprising became known as the Natives. Our Fringe team is stuck in Amber, but they get Walter out. Also, Peter is introduced to his 20+ year old daughter!

In 'WORLDS APART,' we're back to the usual timeframe, with the old foe's game plan now being put into action. They figure out they have to shut the bridge to the two worlds down - for good! In the two-part season ender, 'WORLDS APART,' in Part 1 23 people suffer spontaneous combustion due to nanobytes on their skin. But it's all part of a bigger plan. But, more importantly, the real puppetmaster is revealed! Olivia's powers start to grow within her, and one of the main characters is shot. In Part 2, I won't give anything away, but everything gets sorted out, one way or another - and the teaser for the final seaason 5 is born too!

I can't say enough of this series through here. If you like a good detective story investigating the paranormal, look no further. These are all Widescreen Presentations (1.77:1) enhanced for 16x9 TVs and comes with the Special Features of:

A World Without Peter Featurette
The Observers Featurette
Beyond the Comic Book Featurette
Gag Reel