First things first; the nature of Sundance buzz meant that I missed three of this year's most talked-about narrative titles – Fruitvale, The Spectacular Now and Ain't Them Bodies Saints – while I also failed desperately to catch up with This Is Martin Bonner, The Moo Man and quite a lot of the midnight movies. However, I did manage to see the hot sale of Sundance 2013, and what a letdown that turned out to be. Directed by Nat Faxon and Jim Rash, The Way, Way Back couldn't be more of an obvious Sundance pitch if it was called Little Miss Bunshine. It reunites Steve Carell and Toni Collette in a coming-of-age story, this time involving a teenage boy, Duncan (Liam James), who's on holiday with his mother (Collette) and her dreadful new boyfriend (Carell) at the latter's beach house. Finding himself excluded from the local social scene, Duncan encounters a shabby but cheerful water park, Water Wizz, where he is embraced by the eccentric manager (Sam Rockwell).

Though it's always delight to see Rockwell on such goofy form, especially on a leash as long as this, The Way, Way Back has very little else to recommend it. Maybe it's because I saw it after the film's much-ballyhooed $10m sale to Fox Searchlight, but, even now, only a week after I first clapped eyes on it, it's hard to remember anything about it, whether it's the mild comedy or the threadbare modern-family drama. For a much better theme-park movie, I'd recommend seeing Randy Moore's Escape From Tomorrow (pictured) – except you may not get the chance, if Walt Disney's legal team decide to put the mockers on it. You see, Escape From Tomorrow was filmed entirely without permits at Disney World in Florida, telling the story of a family man who decides to take his wife and two children to the famous resort on the day he finds out he has just been fired.

Guerilla filmmaking suggests cock-eyed camera angles and video grain, but Moore's film is filmed in almost pristine monochrome. An unexpectedly decent post-production budget also allows for some pick-up shots using back-projection, which gives the film a very weird retro quality – not, surprisingly, like a ’50s sci-fi but more like a ’50s melodrama, since the film it most reminds me of is Douglas Sirk's There's Always Tomorrow, with Fred MacMurray and Barbara Stanwyck. This comes from Roy Abramsohn's central performance as Jim White, an everyman whose eye wanders at every opportunity. Although devoted to his kids, Jim becomes obsessed with two French teenagers skipping through the park, and a chance encounter with a predatory single (or perhaps not) mother takes the film into more surreal, David Lynch-like territory.

Whether or not Disney's lawyers pursue it, Escape From Tomorrow may not have a very lucrative commercial life anyway, since its strangeness veers off in several directions, including an offbeat subplot about tech company Siemans running a mind-control programme in the Epcot Centre and another featuring a bizarre strain of cat flu. Nevertheless, it is a captivating experience made all the more absorbing by a score that weaves pre-existing work by Bernard Herrmann and Zbigniew Preisner in with original work by composer Abel Korzeniowski. I have no idea (yet) what it all means, but there is certainly something weird, wonderful and unnervingly timeless here.

Another film that caught my curiosity and attention was Blue Caprice by Alexandre Moors, a chilling true-crime story based on a series of motiveless gun murders in Washington DC, Maryland and Virginia (also known as the Beltway sniper attacks) that took place in 2002. Though it looks beautiful, Moors' film is a tough watch, since it offers no explanations, instead exploring the insanely true father-son relationship between John Allen Muhammad (Isaiah Washington), a divorced father of three, and Lee Boyd Malvo (Tequan Richmond), a Jamaican-born youth Muhammad “adopted” in Antigua. This connection is unlikely enough, but what follows beggars belief: falling under the increasingly paranoid Muhammad's influence, Malvo becomes an obedient and equally obsessed accomplice, firing guns and reading up on war theory. Muhammad proposes a reign of terror that will kill six random white people a day for 30 days, and after customising a saloon car – the Caprice of the title – to allow Malvo to shoot through a hole in the trunk, the pair take to the road.

With little in the way of traditional exposition, Moors' film doesn't so much develop as unfold, and there are few flashpoints to prepare the viewer for what's coming. Muhammad even seems sympathetic at times, and his desperation to reconnect with his kids is made almost palpable in Washington's low-key performance. As Malvo, Richmond is simply a blank page, and how he guilelessly absorbs Muhammad's insanity is the film's central concern. So much so that when the modified Caprice takes to the road, the film practically becomes a horror movie: one can't quite figure out how it came to this, but it did, and pretty soon the victims are falling just as surely as they did in real life, with a blood-freezing, unstoppable and relentless finality.

Like Escape From Tomorrow, Blue Caprice is unlikely to break out into the mainstream. But both films offer real evidence that the Sundance film festival continues to be relevant, and in the absence of such crossover monsters as Beasts Of The Southern Wild, The Blair Witch Project and Little Miss Sunshine, such provocative, minor-chord projects bode well for the rest of 2013.