Imposter at work: when fact becomes stranger than fiction

In Alexander McCall Smith’s The No 1 Ladies’ Detective Agency, the heroine is engaged to investigate a doctor who shows exceptional skill on some days, then fails to diagnose straightforward matters on others. Investigation reveals identical twin brothers, one qualified, the other not, sharing a job.

This scenario is not confined to fiction. Similar incidents occur with surprising frequency in the UK. A former minicab driver was convicted in 2005 after practising as a doctor for five years. Reports stated he had bought a PhD for £12,000 and assumed the identities of a former trainee doctor who had let his registration lapse and of a Spanish psychiatrist.