As machine learning has become increasingly ubiquitous, there has been a growing need to assess the trustworthiness of learned models. One important aspect to model trust is conceptual soundness, i.e., the extent to which a model uses features that are appropriate for its intended task. We present TruLens, a new cross-platform framework for explaining deep network behavior. In our demonstration, we provide an interactive application built on TruLens that we use to explore the conceptual soundness of various pre-trained models. Throughout the presentation, we take the unique perspective that robustness to small-norm adversarial examples is a necessary condition for conceptual soundness; we demonstrate this by comparing explanations on models trained with and without a robust objective. Our demonstration will focus on our end-to-end application, which will be made accessible for the audience to interact with; but we will also provide details on its open-source components, including the TruLens library and the code used to train robust networks.