Absent from prodigious critical scholarship about the seas is a discussion of modernism between the wars. Yet this period is rife with writing set on the waters. This essay argues that it is in their orchestrations of the waters as dead zones that such works revitalize seafaring literature and broaden our understandings of modernism generally. By way of illustration the essay examines the British author James Hanley’s 1938 novel Hollow Sea, which centers on a merchant ship turned troopship during World War I. In its staging of maritime technologies and infrastructures, Hanley’s text ironizes the literary trope and geopolitical concept of the “free sea” from an interwar perspective. The novel’s particular mode of hydro-criticism manifests in its formal challenges to both the war optics of the British state and the optics of a major modernist writer of the seas, Joseph Conrad.