BTTF Part IV in 2015?
few years ago I was 88% CERTAIN theyd do a part 4 for 2015 (as its such an important year in the BTTF mythos and all the actors are the correct age for 1985) with Marty Jnr (played by some young guy), with CLloyd, MJF (cameo), and a returning Crispin Glover, as well as Lea Thompson, Thomas F. Wilson, Elisabeth Shue, Mary Steenburgen, James Tolkan, Marc McClure, hell even Billy Zane! Directed by Zemekics again like Spielberg doing Indy 4 (not necessarily kicking off a new trilogy but there could be - maybe filmed back to back like LOTR or BTTF2/3). Itd be a return to the crazy alternate reality stuff of BTTF2 (which is very much in vogue now - Star Trek09, XM:DOFP, TGEN) involving Marty Jnr finding something the Doc left behind (maybe a prototype time machine he made before the Delorean - a fridge perhaps?) and accidently going back from 'our' non hoverboard 2015 (easily explained via alternate realities/timelines) to 1985 and interacting with Marty & Co (like BTTF2 had Marty interacting with BTTF1 scenes. And like Part 1 showed 80s audiences the 50s, Part 4 would show todays audiences the 80s) and maybe a few other periods (1955 again, hoverboard 2015) screwing around with everything resulting in the trilogy being under threat of being 'erased' and all the cataclysmic consequences that would bring about. Therd be a CG 1985 Marty/MJF for a very brief cameo scene, but Martys parents, Biff, Doc etc were supposed to be 30 years older in the 1985 parts of BTTF1 so no need for make up now, and they could bring in a young lookalike actress for 85 Jennifer no problem as she's already been recast (and if they all appear in 2015 theyd have to be aged up of course like they were in BTTF2 - except MJF/Shue)
now 2015 has been and gone and no Part 4 which is strange considering BTTF is more popular than ever (especially Part 2) and the anniversaries. And especially when everything is getting remade or sequels or prequels now (in the case of time travel stuff its all 3). BTTF is one of the few franchises untouched (despite it being one that would make more sense to continue than others). I guess maybe it could happen in 2020 as they'll need to create new instalments to maintain the franchise just like other 80s series like SW, Indy, Ghostbusters etc (although unlike GB, BTTF would have to be a continuation of the originals in some form as like Star Wars/Trek etc its too popular to simply 'throw out' the originals and remake)