Portal was the first television experience to use Machinima for the majority of the show.
Dave's first major problem - and the inciting event for the storyline - is an attack by an unknown force named The Ultimate. The Ultimate is not known as anything but a nebulous force of evil for most of the show.
During this time, Dave has also been wrangling with other issues. The Drifter, Portal's resident hero, has been tracking down The Ultimate's most powerful agent, Darwin. Darwin is eventually defeated with a trick poison. Grooter, the lovable redneck, falls in love with an equally backwoods Yoodle, and his rescuing her serves as a method to showcase various dungeons in these online worlds - like many of the adventures do.
These rescues culminate into a climax when the Ultimate captures Yoodle and threatens to kill her if Dave does not surrender. Grooter attacks Dave out of desperation, and Dave gives in to The Ultimate. For one episode, Dave is confined to eternal slavery in the "Lavatory of Filth", where he is forced to scrub an ever-soiled toilet. It turns out that in the end, The Ultimate actually intends to inhabit Dave's body and wreak havoc with Dave's power. Rick, Dave's body-swapping hippy spiritual advisor, and Grooter team up to find and free Dave's spirit, while The Ultimate - now inhabiting Dave's body - is repeatedly dunked into the eternally filthy toilet for his treachery. Rick is able to coax The Ultimate out of this torture by leaving Dave's body, trapping him instead in the body of a Myconid, Rick's former vessel. For much of the next season he is effectively benign.
A new force arrives later, though, one more deadly than the Ultimate ever could be. Apex, an even more mysterious character, is a force that had hencetoforth been heard of only in the upper echelons of evil. The Drifter knows of him only the riddle that he has heard:
"He speaks with no sound, and his word is law."
The mystery is soon solved when Apex presents himself to the Hub. With his clown-servant Truggy, he uses his frightening powers of mind control to systematically destroy the Portal team. Beloved movie star Dirk Ruddy is ruined when Apex forces him to admit to being a bedwetter and communist -
With VAL acting as the dummy, Dave takes up a ventriloquism act that he hopes will succeed in getting him enough money to make it to his safehouse. He seems unsure of his performance, though.
"VAL, I'm starting to think I'm the dummy. No one's gonna pay the kind of money we need for a ventriloquist act. D'you think Hollywood's so desperate for mediocre comedy that some dipwad superagent is just gonna show up backstage with a briefcase full of cash?" At this point, exactly that happens. "How you doin'?"
Dave and VAL return to the Hub, and enlisting the aid of Rick, free the Ultimate from his fungal prison and allow him to utilize the Hub's weaponry to attack Apex. With Apex in a serious coma and the Ultimate again free, the stage is set for a cycle to return.
The Ultimate decides to inhabit the body of the very same ventriloquist doll that Dave and VAL had used. The Ultimate is not seen for many episodes after this. Instead, Dave is focused against Bob Klaws, a radical environmentalist who seeks to destroy Christmas because of its wastefulness. Bob, enlisting the help of the now-homeless Truggy, sets up an elaborate plot to kill Santa's elves by making them run over the edge of a cliff, via the creation and usage of a magical flute - not unlike lemmings. Two monsters, Nancy and Murray, accepted this quest. While they murder and ravage the countryside in search of the necessary artifacts, detective Moe Tuesday follows clues to their location and is ultimately attacked, hospitalized, and dies. The plot of the flute is foiled, however, and Dave personally gives Bob Klaws a severe beating. The Christmas shenanigans do not stop there, but the show's final plotline begins there.
It is soon discovered that Bloody Dove, one of the show's more beloved and temperamental characters who had been recently murdered, was actually The Ultimate. He invites Dave for a meeting on Earth. Fully prepared with his Ion-BatTM, Dave enters the studio location. After a short introduction to the Ultimate's fellow toys: Little Miss Damnation, Zozo, Mr. Tickles, and He Who Bathes In Death, Dave proceeds to utilize his bat on the Ultimate and his companions. After the thrashing is complete, a television near Dave turns on. The plot with Bob Klaws (who looked suspiciously like Santa) and the toys was all a ploy. By videotaping Dave's actions, he had created a video that made it look as if Dave actually intended to destroy Christmas. Dave narrowly escapes death when a mob of angry citizens attacks him.
The Ultimate then proceeds to possess Zaitrion, a shapeshifting robot The Drifter has been attempting to locate and destroy as all this is going on. After doing battle with and defeating The Drifter, The Ultimate attacks and destroys the Hub, and again begins destroying the lives of Dave's friends. When his brother and sister, Sunny and Snuggy Dove, attempt to soften the maniacal Ultimate, it is discovered that Bloody's craze - and Sunny's optimism - both stem from the pervasive, sickening cuteness that surrounds Snuggy. The exposure to Snuggy only serves to drive The Ultimate into complete madness, changing his focus from interdimensional domination to destruction of the known Universes.
Stricken with amnesia, Dave attempts to survive in a world out to get him. He is found, captured, and sent to prison for trying to destroy Christmas. Only the occasional flashback haunts him - hints of electricity - hints of some deep secret that had been alluded to in previous episodes. Dave, unable to recall who he is, intentionally botches his trial to hope that he can be killed by electrocution. He thinks this sole memory of his may hold the secret to his past. Afterwards, he finds that the electric chair has been done away with in that jurisdiction. Just as his gas chamber begins to fill, Dave is teleported away, rescued by VAL and various others. He suddenly is reminded of who he is and what his mission is. VAL, Dave, the Drifter, and others make a last ditch effort to destroy The Ultimate, who is lamenting on his life before he teleports off to the Hub's broken remains. Berney the Burynai, Dave's best friend who had been captured and enslaved by The Ultimate, makes a sneak attack and pushes the Ultimate off the tower. They narrowly escape the multimegaton explosion he creates, and return to Earth.
The final episode of Portal was quickly shot, and Dave was given little notice that his show was being cancelled. The episode wraps up various loose ends of the storyline, and ends with a lamentation and allusion to the sudden cancellation of the show.
Larry, a somewhat minor character, was noted for always wearing a wedding dress. This is a reference to Larry the Wedding Dress Guy, a seller on Ebay who was noted for wearing his ex-wife's wedding dress in the photographs for his sale.
Episodes of VBS (a supposed virtual broadcasting system for television in online worlds) were shown on two occasions, demonstrating such "original programming" as Meinfeld, Harborwatch, Trapper Extremioso, and The Trek. These were parodies of Seinfeld, Baywatch, Survivor, and Star Trek, respectively.
Shorty the dwarf, one of the more popular Portal characters, was a parody of Gimli the dwarf from The Lord of the Rings series. Shorty's most distinguishing characteristic was his ability to survive everyday life uttering only the phrase, "You Have My Axe." One special segment—The Life of Shorty—ended in a rock video performed by him—a Portal favorite.
Two "clubs" were supposedly formed during Portal. S.M.U.T.L.U.V., or "Strong Men Unafraid To Like Unicorns Visibly", and S.L.E.A.Z.E.P.I.L.E., or "Strapping Lads Eager And Zealous to Express Pixie Infatuation Laughingly Exposed". One particularly popular episode, the introduction of S.M.U.T.L.U.V., produced interesting responses when Dave interviewed biker gangs about their enthusiasm towards joining the club. Most were interested only because of the club's acronym, though some expressed an interest in the affairs of unicorns.
As of March 26, 2008, the Portal webisodes have yet to be on G4TV.com.
G4TV has announced the return of many old G4 shows, back by popular demand. Among these shows is Portal. The first airing was the 5th of June, with the first two episodes airing back to back 9:30 A.M. and 10 A.M. It will be a part of G4 Rewind, which started June 2nd.