Mirren, McKellen shine in ‘The Good Liar’

Based on novelist Nicholas Searle’s best-selling 2016 debut, “The Good Liar” is a silly breeze of a movie starring two of Britain’s finest actors, each having a blast playing cat-and-mouse with the other.

Ian McKellen charms as Roy, a London con man who woos elderly women into signing their savings over to him. His target here is a seemingly unwitting widow he has met through an online dating service, Betty, played by the ever-delicious Helen Mirren.

The only question is when the rug will be pulled out — not from under Betty, but from under us.

On their first date, there are already hints that all is not as it seems, when Roy and Betty both confess to using fake names on their dating profiles. After the evening is over, Roy introduces us to the unsavory sideline he runs with his accomplice: It’s a scheme involving an offshore investment opportunity and some Russians.

There are a couple of problems with this adaptation by screenwriter by Jeffrey Hatcher (“Mr. Holmes”), which largely sidelines Mirren as it focuses more and more on Roy’s other cons. But an even larger issue arises: Despite Betty’s lack of dialogue, no reasonably attentive filmgoer ever would imagine her — a retired Oxford professor who casually reels off her millions in assets — to be the easy mark that Roy expects her to be.

How Hatcher unknots all of the movie’s various twists is less than satisfying.