It’s possible that as a species we’re simply unable to ever get sick of Sherlock Holmes. Guinness World Records declared him history’s most frequently portrayed literary human character in film and TV — Dracula being the most frequently portrayed non-human character — and that was back in 2012, several Holmses ago. This new one is an old one: an imagining of the super-sleuth in his final years, played by Ian McKellen in a welcome reunion with his Gods and Monsters director Bill Condon. Jeffrey Hatcher adapts Mitch Cullin’s novel A Slight Trick of the Mind, finding Holmes retired to Dover for quiet days of doddering and beekeeping. He has a brusque housekeeper played by Laura Linney, and she has a curious son played by Milo Parker. It so happens that the old man comes to revisit an unsolved case that prompted his retirement, and to seek a secretly yearned-for closure. In truth, the particulars here aren’t terribly compelling, but there is something to the general idea of Holmes having a Spock-like arc — beyond mere logic, and out from under his own myth, with grief and regret. Not that advancing age is the only thing; in fact young Mr. Parker’s is the freshest acting in the movie. Linney, never unwelcome, seems nonetheless shuttered into her safe zone. As for McKellen, well, even when he bunts, he kinda hits it out if the park. Is that a power to defy physics, or a charity from fellow players? Anyway, Condon does a fine job stewarding the basic satisfaction to be had from this casting. The only pressing Sherlock mystery that remains: Who’s up next to play him?