I've been reading here and there for several years about a project called "Topiary" but that apparently is on hold/abandoned. This article is from last October:

More Accurate Details on 'Primer' Writer/Director's 'Upstream Color'


Quote:

CHUD got the scoop on the film entitled Upstream Color, which is described as a romantic dramatic thriller (a "rom-dram-iller" ?) and was written by Carruth himself who will also direct. Ben LeClair (Nacho Libre, Gentlemen Broncos, Year of the Dog) will produce. Like Primer, the film will also be shot in and around Dallas with production beginning in November and going till the end of January.