Securing the services of McKellen and Mirren, actors who haven't needed first names for a good while by now, as the twin leads will have convinced the backers of this enterprise of already having hit pay dirt before filming began and not having to bother too much with the minutiae of a coherent screenplay. Which The Good Liar duly doesn't: all the duo and audience need to know is that he's a conman and she's his prospective mark. Then we can sit back and watch them go and bounce off each other, which they do effortlessly, keeping us happily glued to the story even while it starts going through too many twists and turns and taking bigger and bigger liberties with credibility. The hackish director should have to cope without thespian stabilisers on his next ride.
6/10