<p>While vast and often remote, the deep ocean is connected to people, communities, and societies through its role in Earth systems, cultural and social attachments, and distribution of benefits and burdens from resource exploitation. The deep ocean is also a unique space and part of the planet, in many ways fundamentally different from shallow seas. This article explores these differences from the perspective of the social sciences and humanities and argues that the deep ocean presents unique research questions for these disciplines, in the same way that deep-ocean ecosystems require natural-science approaches profoundly different from those employed in shallow seas. To date, the deep ocean has been seen as beyond social influence and importance, with some sector-specific exceptions. With impacts from human activities expanding, there is a growing need to understand relationships between deep-sea environments and people and societies. In this light, we examine the relevance and potential of the deep ocean as a category for social sciences and humanities research. The study makes the case for establishing more fine-grained perspectives within the broader domain of marine social sciences and humanities that account for the unique characteristics of the deep ocean and the distinct human relations to this vast environment.</p>