In gratitude to Antoine Skoulios for original and illuminating insights on complex materials, and, to celebrate the emergence of his new adventures, this article is a synopsis of astonishing observations made about a decade ago on a deceptively simple material, succinonitrile, during its crystal growth from a curved phase boundary traveling in narrow channels. For a range of pulling speeds, v, v(c1) < v < v(c2), the flat interface transforms, first, to a curved one, then, to a cellular one by groove propagation. The shape of the lead groove is Gaussian, consistent with a linear concentration gradient across the interface, and the pattern has a well-defined wavelength. When v < v(c1), the interface remains flat and when v v(c2), the pattern is time dependent.