Tesla just dropped word yesterday that a drivable prototype of its Model S sedan would be unveiled on March 26th, but the automaker has now gone one step further and let loose the first official teaser image of what we can only assume is said prototype. In true teaser fashion, there isn't a whole lot to see, but as AutoblogGreen points out, it is fairly evident that the Model S is at least shorter than the rival Fisker Karma, and it seems to boast a larger passenger compartment to boot. Hit up the link below to check out a higher res shot, and don't be surprised if Tesla continues to tease this one out right up until that March 26th launch date.