So, the Sherlock's little sister bandwagon rolls on, and this time she's getting married to a toff on Malta, which of course immediately gets derailed by her brother being kidnapped. Directorial duties have now been handed over to the man behind the estimable Boiling Point and Adolescence, so it could be supposed that there'd be a concomitant shift to seriousness after the enjoyable frivolity of the first two films. But instead the change of setting away from the vividly-realised Victorian London of parts I and II robs the enterprise of much of its charm, which it doesn't compensate for with a thin plot with little proper detective work, flabby action sequences and a vague anti-imperialist message. The lively performances and dialogue are still there, but the franchise really can't keep going on the strength of these alone.
5/10