Passing the PLAB test is one of the ways in which an individual can satisfy the General Medical Council ( GMC ) that they have the knowledge and skills which are necessary to practise medicine in the UK. The General Medical Council must assure itself that the particular individual should have suitable qualifications and abilities before it could grant an individual limited registration. Limited registration will allow the individual to practise in the UK in supervised employment in the National Health Service.
Please note that from what I learnt that with the recent changes in law in the UK it is now more difficult to get residency or whatever they call it there if you are an IMG and a non-european citizen, even if you passed the PLAB.