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We present VLA HI spectral line imaging of 5 sources discovered by ALFALFA.These targets are drawn from a larger sample of systems that were not uniquelyidentified with optical counterparts during ALFALFA processing, and as suchhave unusually high HI mass to light ratios. These candidate "Almost Dark"objects fall into 4 categories: 1) objects with nearby HI neighbors that arelikely of tidal origin; 2) objects that appear to be part of a system ofmultiple HI sources, but which may not be tidal in origin; 3) objects isolatedfrom nearby ALFALFA HI detections, but located near a gas-poor early-typegalaxy; 4) apparently isolated sources, with no object of coincident redshiftwithin ~400 kpc. Roughly 75% of the 200 objects without identified counterpartsin the $\alpha$.40 database (Haynes et al. 2011) fall into category 1. Thispilot sample contains the first five sources observed as part of a largereffort to characterize HI sources with no readily identifiable opticalcounterpart at single dish resolution. These objects span a range of HI mass[7.41 < log(M$_{\rm HI}$) < 9.51] and HI mass to B-band luminosity ratios (3 <M$_{\rm HI}$/L$_{\rm B}$ < 9). We compare the HI total intensity and velocityfields to SDSS optical imaging and to archival GALEX UV imaging. Four of thesources with uncertain or no optical counterpart in the ALFALFA data areidentified with low surface brightness optical counterparts in SDSS imagingwhen compared with VLA HI intensity maps, and appear to be galaxies with clearsigns of ordered rotation. One source (AGC 208602) is likely tidal in nature.We find no "dark galaxies" in this limited sample. The present observationsreveal complex sources with suppressed star formation, highlighting both theobservational difficulties and the necessity of synthesis follow-upobservations to understand these extreme objects. (abridged)

The ALFALFA "Almost Darks" Campaign: Pilot VLA HI Observations of Five High Mass-to-Light Ratio Systems