Unless you've been stuck under a sandrock on the desert planet of Tatooine, you know that May 4 is Star Wars Day.

So let's celebrate like an all-nighter at the Mos Eisley Cantina! (And May the Fourth be with you!)

This fan-driven holiday holds special significance this year as geeks from here to Dagobah await the release of "Star Wars VII: The Force Awakens."

The J.J. Abrams-helmed megaproject won't land until Dec. 18, but the series' overlords (goodbye, George Lucas, hello, Disney!) have been ramping up the anticipation like a rancor fight in Jabba the Hutt's palace. The second movie trailer debuted last month to 88 million online views in the first 24 hours (a record). The 2-minute preview fired off a nonstop barrage of new scenes faster than the Millennium Falcon — climaxing with the return of 72-year-old Han Solo and an ageless Chewbacca.

You could almost hear multiple generations of fans gasp for breath.

But we've been fooled by trailers before. The "Star Wars" series is beloved beyond all other fantasy franchises. And there is a new hope that the seventh episode will be a return to Jedi form. But when you take a serious look back at the first two trilogies, the quality can be more uneven than C-3PO's gait.

To bring you up to lightspeed, let's take a look at the movies' greatest triumphs and most memorable follies.

Or as we call them: the light side and the dark side.

'Star Wars: A New Hope' (1977)

Light side: It was a generation's "first step into a larger world." An iconic villain, Jedi philosophy, droids, a strong female lead, and John Williams' score.

Dark side: Lucas' tinkering with the Special Editions proved to be too much of a good thing. Han shot first. And true fans know it.

Rottentomatoes.com score: 93%

'The Empire Strikes Back' (1980)

Light side: The first sequel is as close to a perfect sci-fi space opera as you can get. The battle of Hoth. AT-AT Walkers. Boba Fett. Master Yoda. Lando. The cliffhanger ending. And that dialogue! "I love you." "I know."

Dark side: Really?

Rottentomatoes.com score: 96%

'Return of the Jedi' (1983)

Light side: Luke completes his journey from farm boy to Jedi master — and he has the new wardrobe and lightsaber to back it up.

Dark side: They didn't seem so bad in grade school, but over the years those cuddly Ewoks have revealed themselves to be that generation's Jar-Jar.

Rottentomatoes.com score: 79%

'The Phantom Menace' (1999)

Light side: After more than a decade of waiting, the movie's stunning trailer (Darth Maul! Pod racing! Liam Neeson!) sets the bar high.

Dark side: Instead, we got racist caricatures, a plot better suited for C-SPAN and a wooden little boy. "Yippee!"

Rottentomatoes.com score: 57%

'Attack of the Clones' (2002)

Light side: After the dialogue-heavy Episode I, we get to see the Jedi in action — including CGI Yoda and Samuel L. Jackson. And they don't disappoint.

Dark side: The melodrama between Anakin and Padme is so bad it makes a Nicholas Sparks movie look like Shakespeare.

Rottentomatoes.com score: 67%

'Revenge of the Sith' (2005)

Light side: After decades of anticipation, fans finally get to witness the epic lightsaber battle — inside a volcano — they've been waiting for, and witness the birth of a legend.

Dark side: But then all of the magic is undone with one drawn-out word: "Noooooooo!"

Rottentomatoes.com score: 80%