A tokamak plasma vessel comprising: a toroidal plasma chamber; a plurality of poloidal field coils; an upper divertor assembly; a lower divertor assembly; wherein the plurality of poloidal field coils are configured to provide a poloidal magnetic field having a substantially symmetric plasma core and an upper and lower null, such that ions in a scrape off layer outside the plasma core are directed by the magnetic field past one of the upper and lower nulls to divertor surfaces (321,322,323,324) of the respective upper and lower divertor assembly; wherein: each of the upper and lower divertor assembly comprises: an inboard strike point divertor surface, located at the inboard strike point; an outboard strike point divertor surface, located at the outboard strike point; an inboard far divertor surface, located radially inwards of the inboard strike point divertor surface; an outboard far divertor surface, located radially outwards of the outboard strike point divertor surface; and at least one private divertor surface (805,806), located between the inboard and outboard strike point divertor surfaces; each far divertor surface and/or each private divertor surface comprises: a liquid metal inlet; and a liquid metal outlet located below the liquid metal inlet; configured such that in use liquid metal flows from the liquid metal inlet to the liquid metal outlet over at least the respective divertor surface. a toroidal plasma chamber; a plurality of poloidal field coils; an upper divertor assembly; a lower divertor assembly; wherein the plurality of poloidal field coils are configured to provide a poloidal magnetic field having a substantially symmetric plasma core and an upper and lower null, such that ions in a scrape off layer outside the plasma core are directed by the magnetic field past one of the upper and lower nulls to divertor surfaces (321,322,323,324) of the respective upper and lower divertor assembly; wherein: each of the upper and lower divertor assembly comprises: an inboard strike point divertor surface, located at the inboard strike point; an outboard strike point divertor surface, located at the outboard strike point; an inboard far divertor surface, located radially inwards of the inboard strike point divertor surface; an outboard far divertor surface, located radially outwards of the outboard strike point divertor surface; and at least one private divertor surface (805,806), located between the inboard and outboard strike point divertor surfaces; each far divertor surface and/or each private divertor surface comprises: a liquid metal inlet; and a liquid metal outlet located below the liquid metal inlet; configured such that in use liquid metal flows from the liquid metal inlet to the liquid metal outlet over at least the respective divertor surface. each of the upper and lower divertor assembly comprises: an inboard strike point divertor surface, located at the inboard strike point; an outboard strike point divertor surface, located at the outboard strike point; an inboard far divertor surface, located radially inwards of the inboard strike point divertor surface; an outboard far divertor surface, located radially outwards of the outboard strike point divertor surface; and at least one private divertor surface (805,806), located between the inboard and outboard strike point divertor surfaces; an inboard strike point divertor surface, located at the inboard strike point; an outboard strike point divertor surface, located at the outboard strike point; an inboard far divertor surface, located radially inwards of the inboard strike point divertor surface; an outboard far divertor surface, located radially outwards of the outboard strike point divertor surface; and at least one private divertor surface (805,806), located between the inboard and outboard strike point divertor surfaces; each far divertor surface and/or each private divertor surface comprises: a liquid metal inlet; and a liquid metal outlet located below the liquid metal inlet; configured such that in use liquid metal flows from the liquid metal inlet to the liquid metal outlet over at least the respective divertor surface. a liquid metal inlet; and a liquid metal outlet located below the liquid metal inlet; configured such that in use liquid metal flows from the liquid metal inlet to the liquid metal outlet over at least the respective divertor surface.