Ian McKellen gives a strikingly subtle performance as an aged Sherlock in Mr Holmes

Based on Mitch Cullin's novel A Slight Trick of the Mind and set in 1947, it imagines Holmes as a 93-year-old retiree and enthusiastic beekeeper, living in Sussex with his beleaguered housekeeper Mrs Munro (Laura Linney) and her sweet son, Roger (Milo Parker). Physically frail, his memory is giving out and he's struggling to piece together the fragments of his final case involving Thomas and Ann Kelmot (Patrick Kennedy and Hattie Morahan) ‑ the reason for his departure from Baker Street and exit from the sleuthing profession.

https://www.youtube.com/watch?v=KSsf17Exa4g&showinfo=0

Mr Holmes presents various flashbacks that at first interrupt the film's flow but actually serve as intriguing titbits, building a convincing picture of a man haunted by scattershot, out-of-context memories. They take us to Japan, where Holmes seeks out the prickly ash plant in an effort to stem his senility; to his brother Mycroft's London club, where receipt of the complete Sherlock Holmes stories forces him to confront his own legend; and they show him many years earlier in pursuit of the enigmatic Ann, in scenes which recall Hitchcock's Vertigo. Back in the present, he finds a friend in young Roger, who takes an interest in the bees and shows an aptitude for deduction; Holmes shares with him the details of the Kelmot case in instalments, as each development returns to him.

Condon's CV could hardly be more eclectic (Candyman: Farewell to the Flesh, Dreamgirls, Kinsey and the final two parts of the Twilight saga). The obvious antecedent among his work is the Oscar-winning Gods and Monsters, his James Whale biopic, which also featured McKellen and depicted a genius at the end of his life, sparring with his housekeeper and reflecting on his past. Mr Holmes lacks the masterful judgement of that film but moves with the care of its elderly protagonist and sports a cool, unflashy elegance.

McKellen has a multifaceted face as compelling as any narrative and, assisted by Tobias A Schliessler's sensitive cinematography which seems to accentuate every facial line, he communicates Holmes's complex psychology with striking subtlety and by showcasing an enjoyably broad range of scowls, scoffs and sneers. McKellen convincingly inhabits both the fearful, frustrated and sadly diminished Holmes and the dashing, pre-retirement detective, with the sight of him in his top hat and tails offering up an alternative iconic image to rival the deerstalker and pipe (an invention of Dr Watson's).

The lively, astonishingly believable Parker makes for an endearing companion, Morahan is heartbreaking and, although Linney's wobbly accent distracts, she delivers dramatic conviction aplenty. Furthermore, the film delights in tiny details: the way an eye-catching hat blooms in a garden as if it were a flower, and there are interludes of knowing humour (Frances de la Tour adds a touch of 'Allo 'Allo! absurdity as glass harmonica instructor Madame Schirmer; Holmes heads to a melodramatic film adaptation of the case he's trying to recall, where he's played by Nicholas Rowe, star of 1985's Young Sherlock Holmes).

Mr Holmes resists the sensational reveals of traditional murder mysteries, opting instead for a series of moving conclusions. The ponderous pace and initial lack of focus will prove testing to some but this is a slow, steady film that builds in power almost imperceptibly, working its way deep under your skin.

Mr Holmes is released in cinemas on Friday 19 June

Buy your copy of Radio Times Guide to Films 2015 from the RT shop