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C-2019 Q4 (Borisov) is the first interstellar comet and only the second interstellar object (after .Oumuamua) ever identified within the solar system. We propose high resolution observations with WFC3 and HST in order to probe the development of this body in Cycle 28. During this time we will use HST and WFC3 to constrain the nucleus and dust properties. Observation as the Earth passes through the projected orbit plane early in the Cycle will provide a model-free estimate of the dust extent and velocity perpendicular to the plane. Additional comma spaced observations provide perspectives as the object recedes from about 9 to about 13 AU. The high resolution of HST is needed to resolve faint near-nucleus structures (jets comma fans) and fragments at the growing distance to the comet. The proposed observations extend the temporal coverage of the evolution of this unique object and take advantage of new perspectives.