Atomically thin graphene holds exceptional promise to enable new functionalities and drastically improve performance of electronic, energy, sensing, and bio-medical devices. One of the most promising approaches to device-compatible graphene synthesis is chemical vapour deposition on a copper catalyst; this technique however is limited by very high temperatures (∼900 °C) and a lack of control as well as post-growth separation from the catalyst. We demonstrate and explain how, through the use of a plasma, a graphene film containing single layer graphene can be grown at temperature as low as 220 °C, the process can be controlled and an instant and water-mediated decoupling mechanism is realised. Potential use of our films in flexible transparent conductive films, electrical devices and magneto-electronics is demonstrated. Considering the benefits of catalyst reuse, energy efficiency, simplicity, and environmental friendliness, we present this versatile plasma process as a viable alternative to many existing graphene production approaches.