Chiwetel Ejiofor has just experienced some of the intense struggles of fatherhood. He doesn’t have children of his own, but in his new film — he is director and lead actor in The Boy Who Harnessed the Wind — he plays Trywell Kamkwamba, a Malawian farmer at loggerheads with his son William over how best to save their village from famine. Ejiofor is quiet, cerebral, sitting with his arms crossed in the drawing room of an upmarket London hotel. He has the look of a young professor waiting to hand back a disappointing essay, but his face comes alive when he discusses Maxwell Simba, the newcomer who plays his on-screen son.
“I watched his audition via laptop from the UK and then flew out to
