Donald Sutherland and Helen Mirren in The Leisure Seeker (Sony Pictures Classics)

Where the hell are Mom and Dad? A couple’s middle-aged offspring are flabbergasted to find their parents’ RV permanent parking spot empty: the pair have just gone maverick, taking their vintage 1975 Winnebago on the road for one last fling. Even the name of the van, the Leisure Seeker, sounds like a weird mistranslation, and its journey will prove ill-fated for viewers and the old folks alike.

Donald Sutherland plays an academic with Alzheimer’s, alternately spouting generic praise of Hemingway and childishly pouting for a burger. Helen Mirren is his dotty wife who brandishes a honeyed Southern accent, sports a nylon wig, and conceals a secret beneath her sunny patter. Both actors struggle to bring some personality to well-worn situations and deadbeat dialogue, Mirren a bit harder than Sutherland, but even these pros can’t pump up a busted flat.

The wheels on the bus go round and round as John and Ella careen from Massachusetts toward the Florida Keys to the Hemingway House as the movie panders to the over 60 demographic with every twinkle and wisecrack. Husband and wife cope with incontinence and creaky eldersex, reminisce about their courtship, and look at old photos. They also fall afoul of a cop and later mingle with young folks who think they’re just delightful—it’s almost a relief when two teen varmints try to stick them up, a snafu for which Ella packs a feisty solution. Meanwhile, the couple’s confused grown children bicker over how to bring their parents home. And worry, of course: anyone could see that John is in no shape to take the wheel of any vehicle, let alone a two-ton behemoth that could wipe out anyone or anything in its way.

Director Paolo Virzì and four other screenwriters try to liven up the road trip with two potentially disruptive plot devices. In one, John and Ella come across a Trump rally, a ripe occasion for satire, shrewd observation, or even a few cheap shots. As staged by Virzì, it registers as a harmless barnstorm with no impact on the couple or the story. In the second gimmick, jealous John deludedly hunts down an old flame of Ella’s at gunpoint.  The punch line falls flat and provides a lackluster appearance for the late Dick Gregory, who deserved better in his last movie.

An unexpected ending provides a note of bitter realism to The Leisure Seeker’s meandering journey. By then, you’re relieved that the road trip has ground to an end.