The Claimant solicitors acted for the Defendant clients in fraud/ conspiracy claims brought by Sheik Mohammed. As the Defendants settled with the Sheik on drop-hands terms, depriving the Claimants of any cost recovery, the latter sued their former clients for some £3m, alleging breach of an implied duty of good faith in the retainer. The CA, upholding the Commercial Court, rejected the implication of such a term as it failed to fulfil criteria of business efficacy or obviousness; nor was a solicitor's retainer a 'relational' contract where such a duty might apply.