"Folly" is an expansion of Mathiasen's exhibition shown at O–Overgaden, Copenhagen in 2023, including a series of new works and garden walks, and a satellite exhibition at Pachinko, Oslo. With stop motion animation, drawing and sculpture, Mathiasen examines the relationship between natural surroundings and mental health, looking at the garden's public, institutional, and psychological space – both from a historical perspective and through her own experiences of dealing with mental illness.