Abstract: The involved and intricate analysis of a strong gravitational lens is a complex and computationally demanding problem, but one that when successfuloffers an unrivaled view of the otherwise invisible Universe. Using open-source strong lens modeling software, PyAutoLens, I therefore reveal the contents of the Universe that is otherwise too dark to observe. Exploiting the shearing and stretching of each lensed source galaxy’s light, I dissect the physical structure of their foreground lens galaxy, revealing low-surface brightness stellar halos that, despite comprising the majority of their hostgalaxy’s mass, are too faint to observe. I present the first strong lensing super massive black-hole mass measurement, which arises from a fortuitous lensing geometry where a subset of light rays perturb the lens’s central regions. Finally, I argue that strong lensing is the most compelling tool to study dark matter, both in terms of the mass, ellipticity and density of each lens’s host dark matter halo and the many hundreds of substructures our cosmological model predicts that they contain.