Appearances were made by actors, celebrities and fictional characters such as Danny DeVito and Rhea Perlman as married couple Vic and Paula, Robin Williams as Everyman, Harold Ramis as Elon Spengler (a relative of Dr. Egon Spengler from Ghostbusters), Will Smith as himself, Alex Tebrek as himself and Dustin Hoffman as Everylawyer.
Other characters in the special include:
- Neil Patrick Harris as Doogie Howser from Doogie Howser, M.D.. Doogie is the only character to appear on-screen and to interact with Doc.
- Bugs Bunny, Porky Pig and Tweety Bird from Looney Tunes.
- Dorothy Zbornak, Sophia Petrillo, Blanche Devereaux and Rose Nylund from The Golden Girls.
- The Huxtable family (Cliff, Claire, Theo, Vanessa, Denise, Rudy and Olivia Kendall) from The Cosby Show.
- Kermit the Frog and his nephew Robin.
- Marcy D'Arcy and the Bundy Family (Al, Peggy, Kelly and Bud) from Married With Children.
- Sam Malone, Rebecca Howe, Norm Peterson, Dr. Frasier Crane (who would have his own spinoff show Frasier from 1993 to 2004), Woody Boyd and Cliff Clavin from Cheers.
Elements from Back to the Future
Doc arrived in the DeLorean time machine at the Anytown town square and went to St. Terra Hospital where Mother Nature was kept.
Once there, he showed Doogie Howser and the other doctors several present environmental disasters, including:
- Smoke filling the air.
- Bodies of water being polluted by oil and other chemicals.
- Animals being hunted down.
- Many trees chopped down.
Doc mentioned traveling to 2057 and found that all rain forests were gone. He came back to the hospital room shortly, and discussed his travels to several time periods in the past from before pollution became a problem such as:
- 1631: In which he described having a drink from the Mississippi River as it was clean and pure at the time.
- 1900: In which he was in a little town that he described being nestled in a broad basin, surrounded by beautiful snow capped mountains and had a breathtaking blue sky.
- Despite Cheers being established as a television program in Back to the Future Part II during the scenes at the Cafe 80's, the cast is shown to live in within the same universe as the Back to the Future cast.
- Additionally Back to the Future: Untold Tales and Alternate Timelines #4's story "Emmett Brown Visits the Future" would establish Ghostbusters to be a fictional franchise.
- Carl Sagan appeared in the special as himself to discuss the scientific details behind global warming.
|Organizations and titles||Vehicles||Weapons and technology||Miscellanea|
Weapons and technology