With this week’s “Prometheus,” Ridley Scott returns to the scene of his greatest triumph, the classic sci-fi/horror movie “Alien.”

And he’s gonna mess it up.

Look, Scott’s had a long and respectable career with at least two indisputable masterpieces to his credit (“Blade Runner” being the other), but this whole prequel business is a minefield, cinematically speaking. Historically, looking back and over-explaining things is a recipe for disaster, as these examples show. But, you know, good luck, Ridley

(P.S.: “Batman Begins” doesn’t count as a prequel because it’s the origin story of a series reboot. P.P.S.: I’m a huge nerd.)

THE GOOD

“The Godfather Part II” — Sure it’s sort of a cheat, because it see-saws between Michael Corleone’s consolidation of power after the “Godfather” and young Vito Corleone’s similar journey prior to it. But the DeNiro-as-Brando/Vito stuff is indelibly brilliant and, hey, you try coming up with good prequels

“Twin Peaks: Fire Walk With Me” — Woe to the “Twin Peaks” newbie who thinks it’s a good idea to watch this feature film prequel before the TV series. Congratulations! Everything’s spoiled! Don’t bother! That aside, “FWWM,” while undeniably a mixed bag of some of David Lynch’s best and worst ideas, can boast an Oscar-worthy performance (yeah, I said it) by the underrated Sheryl Lee, as well as some genuine Lynchian nightmare creepiness.

“X-Men: First Class” — The “X-Men” series’ inexorable decline was unexpectedly reversed by this quite respectable tale of the mutant superhero team’s early days. Sure, January Jones’ traditional woodenness is a drag, but Michael Fassbender and James McAvoy bring their A-game to the X-Men’s Magneto and Professor X.

“Indiana Jones and the Temple of Doom” — Taking place before the undeniably superior “Raiders of the Lost Ark” (and thus sticking us with the vapid Kate Capshaw instead of spunky, adorable Karen Allen), this Indy prequel still provides a respectable (and at one point literal) roller coaster ride of fun.

THE BAD

“Star Wars” Episodes I to III —  It’s become clich?o mock these long-awaited, inconceivably disappointing “Star Wars” prequels, but my childhood still cries out for vengeance against George Lucas.

“Butch and Sundance: The Early Years” — This 1979 prequel to “Butch Cassidy and the Sundance Kid” trades Paul Newman and Robert Redford for Tom Berenger and William Katt. Think about that for a moment. Just think about it

“Dumb and Dumberer: When Harry Met Lloyd” — Remember that scene in “Dumb and Dumber” when Jeff Daniels has, um, distress on the toilet? Well, stretch that out to 85 minutes, only with two nondescript young guys doing Daniels and Jim Carrey impressions.

“Gods & Generals” — I didn’t regret a minute of the four hours I spent watching “Gettysburg,” but anyone who actually makes it to the end of this similarly lengthy, un-similarly interminable Civil War prequel should get a medal.

“Alien vs. Predator” and “Alien vs. Predator: Requiem” — We can only pray that Ridley Scott’s return to the “Alien” fold means the end of these limp, toothless sci-fi crossovers.

Dennis Perkins is a Portland freelance writer.