Lennie James recently won a BAFTA for his leading role in the mini-series “Mr. Loverman,” and for good reason: His performance is as whole and mesmerizing a portrait as one sees on television.

Six years before she bagged the Booker Prize for Girl, Woman, Other (2019), Bernardine Evaristo published her seventh novel, titled Mr Loverman (2013). It traces the lives of members of Britain ...