A thin, small muscle with independently innervated units would be a desirable tool to have in the plastic surgeon’s facial reanimation arsenal. The serratus anterior muscle has the potential to fulfill these criteria. Although the serratus anterior muscle anatomy has been studied previously, little attention has been given to the intramuscular anatomy. Slips 5-10 of fifty serratus anterior muscle specimens from twenty-seven cadavers were characterized following intra-arterial latex injection. The nervous, arterial, venous, and muscular microanatomy of the smallest divisible muscle unit (subslip) were studied and recorded. A total of 520 subslips were analyzed. The arterial and muscular anatomy has been reported elsewhere by our group. The principle nerve supply to the muscle is the long thoracic nerve, the branches of which supply different subslips. They follow the artery and divide proximal to the arterial branch points. The relative positions of nerve, artery, and venae comitans with respect to the muscle were consistent as well. From deepest to most superficial, the order was muscle – nerve – artery - venae comitans. Nerve branching morphology was organized as follows: 1) nerve divisions - highest order of branching; 2) common slip nerves - intermediate order; 3) proper slip nerves - lowest order. Amongst the 50 specimens, six different nerve division patterns were noted: the most common was three divisions (16 specimens), four divisions (16 specimens), and five divisions (12 specimens). External neurolysis permitted further separation of nerve branches from one another. The common slip nerve fascicles were separable up to a distance of 2.0 + 1.1cm proximally, resulting in a mean fascicle length of 4.2 + 1.9cm. Following epineurotomy, first nerve divisions gained an average of 2.1 cm (N=53, SD 1.1cm), second divisions gained 2.0cm (N=50, SD 1.1cm), third divisions gained 1.9 cm (N=46, SD 1.1cm), fourth divisions gained 1.6cm (N=25, SD 0.9cm), and fifth divisions gained 1.4cm (N=11, SD 1.1cm). Our findings indicate that serratus slips 5-10 may be separable into individual subslips, each with their own neurovascular supply, each capable of being oriented differently from the others, thus giving the tantalizing possibility of the capacity to create a complex of independent force vectors. The development of this capability may open new avenues for refinement in facial animation.