A single crystal of the boron subhydride B-104.67(4)H-3 was serendipitously obtained while attempting to synthesize beta-boron. An accurate crystal structure analysis revealed a distorted beta-boron framework with the noncentrosymmetric space group R3m. We have found one interstitial site occupied by boron. The site related by inversion remains empty. The distortions of the framework result in ideal environments for the interstitial boron atom, and for the three hydrogen atoms at bridging positions between icosahedral B-12 groups, they result in ideal B-H distances of 1.33 A. B-104.67(4)H-3 is a borane with the lowest amount of hydrogen recorded to date, and it is the first compound with a noncentrosymmetrically distorted beta-boron framework.