so is this one awful compared to part 1 and part 2

IMHO, part 2 is the awful one, due to what transpired between Crispin Glover and Bob Gale.

I love Part 2 and 3 equally. Neither hold candle to the first however.

"See you on the other side, Ray,"
"Nice working with you Dr. Vankman,"

II has a more exciting premise I suppose, but part III is more in tone with the original. It's a comedy but it's not as satirical and campy as II.

They are all great

2 and 3 are close, but I actually marginally prefer Part III

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I thought it was a pretty weak way to end the series since it was essentially just a Western and didn't have the great character drama of the first film or the time travel intrigue of the second. It just seemed like they were tired of making Back to the Future films by that point and didn't have the same enthusiasm they did for first two films.

It's still a great film series, but the third isn't as great as the first and second.

http://uproxx.com/movies/2015/10/back-to-the-future-3-defending/2/

After a lot of Facebook fake-outs, it’s finally, actually Back to the Future Day. While everyone online is celebrating the technical achievements predicted in Part II, tricking out their cars with a Flux Capacitor, and, of course, all things hoverboard, there’s one entry of the franchise that’s too-often brushed aside: Back to the Future Part III, an enjoyable sequel that is an essential entry that bookends the trilogy in a succinct and satisfying way. Indeed, while the original may be a genre-defining classic, and while the second doubles down on the adventure, the third film deserves its own moment of praise.

Capturing The Spirit Of The Original

The third movie repeats the basic premise of the first, taking Marty out of his era, placing him in another, and leaving Marty and Doc confused over how to get back to 1985. The first movie features a search for a 1.21 gigawatt charge to trigger the flux capacitor, and Part III involves a similar search, driven by the need to get the DeLorean up to the required speed of 88 mph needed for time travel. Of course, this being 1885, Doc and Marty have limited resources. And just as plutonium wasn’t easily purchased at the corner drug store in 1955, finding a way of pushing the DeLorean to the necessary speed proves to be quite the challenge.

Shifting The Focus To Doc

The film’s story set itself apart from the others by giving Doc a little room to grow as a character. In the first movie, he helps Marty. In the second, Doc helps Marty while also helping the “other” Marty. Part III turns the tables, putting Doc in the position where he’s the one who needs Marty’s help. Early on in Part III, while still in 1955, Marty notices the headstone with Doc’s name dated just a few days after his Western Union telegram. Rather than simply returning to 1985, he follows him back in time to do what Doc had been doing for him all this time — warning him about his future.

After Doc gets Marty out of a jam (or a noose), Marty’s goal becomes split between fixing the DeLorean while also making sure Doc stays clear of Buford Tannen, Biff’s great-grandfather (who, like all Tannens, is played by Thomas F. Wilson). In addition, Doc gets his own love story when he meets and saves Clara (Mary Steenburgen), which gives him an added dimension, turning him into a deeper character than just the frizzy-haired mad scientist who’s there to tirelessly guide Marty to safety.

A Loving Homage To The American Western

Part III also takes full advantage of its 1885 setting. It’s clearly the work of creators who love Westerns. As director Robert Zemeckis explains in the commentary track of the 2002 DVD release, he and screenwriter Bob Gale had played with the idea of “meeting cowboys” since the early days of the trilogy, but held off until the final installment. The crew rebuilt the set of Hill Valley from scratch, creating a crisp, colorful version of the Old West.

The result is a heartfelt love letter to the genre, from Marty’s chosen moniker of “Clint Eastwood,” the sepia-toned long shots, the Western-tinged homages in Alan Silvestri’s reworked score, and the elaborate climax built around its own spin on the classic train robbery. The film even features actors Pat Buttram, Harry Carey, Jr., and Dub Taylor, who were all famous for their numerous roles in old Westerns, as the “saloon old-timers.” (Also cameoing: ZZ Top, looking not-at-all out of place in 1885.)

Hill Valley Comes Full Circle

By taking us back to the early days of Hill Valley, Back to the Future Part III creates a fuller sense of the town’s history, one that goes back to Marty’s great-grandfather, Seamus (also played by Fox), an Irish-born immigrant who’s come to set up a new life with his wife Maggie McFly (Lea Thompson). It also gives some backstory to the troubled Tannen family through Buford, Biff’s great-grandfather, who was better known as “Mad Dog,” (a nickname he hates).

Over the course of the film, we see the construction of the courthouse, leading up to the memorable moment where Marty and Doc are photographed with the clock for its dedication. It’s an example of how Part III uses Hill Valley’s humble, dusty beginnings to flesh out the world of the films. It does something similar with the characters, too. Marty learns one final lesson from his time in the Old West, and once he returns to 1985, he doesn’t give into Doug Needles’ (Flea) attempt to bait him into a street race. By refusing, he saves himself from the car wreck that weighed so heavily on his future self in 2015, and rights his timeline’s one last wrong. It also gives Doc a nice, sentimental sendoff, showing him happily married to Clara, along with their two children, Jules and Verne, before ending on a moment that shows that where they’re going, they don’t need train tracks.

With that callback to first movie’s unforgettable final scene, Zemeckis and Gale bring their trilogy to a near-perfect conclusion, having told the story of a fully-realized world, and a few of its alternate timelines. Along the way, we’ve seen these characters grow throughout their places within the town’s history — whether they belonged there or not.

Well frankly all of them are good. I can't say anyone get down to the level of Batman and Robin. I think Part 2 is the weakest. I mean its wacky. But i don't think Part 2 had the heart than 1&3 had. Back the Future was Marty's Story. Part 2 to was Biff's Story. And Part 3 was Doc Brown's Story. I think Marty and Doc Brown Stories are just much more interesting.