Shearer and "The Big Uneasy" at the Brattle

If for no other reason, Harry Shearer will be immortalized for "This is Spinal Tap!," which he made with Christopher Guest, Michael McKean, and Rob Reiner and in which he stars as band member Derek Smalls. But he can boast of many more achievements besides, including a documentary about the untold story of Hurricane Katrina -- "The Big Uneasy." It  shows tomorrow (Tuesday) at 7:30 pm at the Brattle Theatre. Shearer himself will be on hand for a Q & A after the screening.

Himself a resident of New Orleans, Shearer was devastated like so many others by this "natural disaster." Or was it entirely a natural disaster? That's the first question he asks in his exhaustive and revelatory film. We all know about the inadequacies of FEMA in handling the aftermath of the storm. But largely ignored has been the cause: the culpability of the Army Corps of Engineers in their inadequate system of levees and pumps. The Corps was much more successful at covering up their guilt than doing their job, as Shearer exposes with damning detail. He also examines another overlooked factor in the flooding -- the erosion of the wetlands that historically have buffered the city from storm damage, a phenomenon ironically caused in part very same levees that  were constructed to protect the city.

Sadly, this is no mockumentary. Though at times lighthearted (with cameo appearances by John Goodman), there's not much to laugh about, and the haplessness exposed is not the comic farce of a befuddled heavy metal band but the injustice and tragedy of institutions that betrayed the people whose lives depended on them.

The Brattle is at 40 Brattle St, Harvard Square. 617.876.6837 or info@brattlefilm.org.