He is an excellent actor , frequently shown to have convinced others that he is someone else -- indeed his first appearance occurs as a gay man whom Molly is seeing .
Someone does not realise someone 's 's identity at the time .
He is an excellent actor , frequently shown to have convinced others that he is someone else -- indeed his first appearance occurs as a gay man whom Molly is seeing , and Sherlock does not realise his identity at the time .