Singapore’s infrastructural treatment of its seas and coastlines derives from the island city’s long-standing anxieties with land limitations. The island’s formerly abounding reef-fringed margins – ephemeral and elusive landscapes that shape-shift within the intertidal zone – have largely been reclaimed. Today, faced with unprecedented challenges, Singapore is reconsidering the importance of the island’s former reef margins to curb future sea level rise. The revival of these margins nevertheless uncovers anecdotal archipelagic-bound histories that blur the distinct relations between above-ground and under-sea – what is seen and unseen – contrasting with technocratic solutions that perpetuate the construction of island edges as a distinct visible line, devoid of the tidally shifting sea. This chapter takes the phantasmic nature of the intertidal reef – the metaphorical and physical condition of a landscape – to perform a storied mode of ‘mapping’. The mapping of the reef landscape by anecdotal evidence postulates that our encounter with the less visible aspects of reef islands rests on affective knowledge. The chapter traces the amorphous boundaries of two remaining reefs on the offshore islands of Pulau Hantu (‘Ghost Island’ in Malay) and the second Pulau Hantu, later renamed Keppel Harbour. Working primarily through storied fragments, we weave these storied remains within the islands’ natural, geological and biological processes to produce affective readings and postulate alternative ways of seeing a phantom archipelago.