Only an acerbic, emotional Lily Tomlin stops Paul Weitz's dramedy from turning into Grumpy Old Woman: The Movie

Substantial roles for actresses over the age of 60 are notoriously few and far between – which immediately makes Grandma, the new film from Paul Weitz, feel a little dangerous. Behind its innocuous-sounding, lace-edged bed-jacket of a title, you can just about make out the glint of lupine teeth.

The film stars Lily Tomlin as Elle Reid, a septuagenarian lesbian poet, whose granddaughter Sage (Julia Garner) arrives at her door one morning and asks to borrow $630 in cash. This very specific sum, we quickly learn, is the going rate for an abortion. And while Sage’s mother (Marcia Gay Harden) is no doubt good for it, the 18-year-old can’t quite face the accompanying lecture and guilt trip.

Elle recently paid off and cut up her credit cards, so has nothing to give her. But sensing a semi-kindred spirit in her granddaughter – perhaps wayward living skipped a generation – she agrees to help, and the two set off on a suburban road-trip around Los Angeles’s more dog-eared fringes to scare up the necessary funds. Among their targets are Cam (Nat Wolff), the baby’s proudly feckless young father, Deathy (Laverne Cox), an old tattoo-artist friend of Elle’s with an outstanding debt, and Karl (Sam Elliott), who was briefly Elle’s husband way back when.

“I thought you always liked women?” puzzles Sage, when she meets the third of these. It’s a reasonable question, to which Elle very reasonably replies: “Yes, but I didn’t always like myself.”

Grandma’s storyline winds down in less than a day, and at only 79 minutes in length, the film unquestionably dices with slightness. But you don’t leave the cinema feeling that something was missing, and Tomlin, who appears in every scene, constructs a persuasive and highly watchable character.

That’s partly because, however low-key the central drama may be, there’s lots going on at the edges of the script. When the film begins, Elle is in the process of splitting up with her younger lover Olivia (Judy Greer): it soon becomes clear that this is at least partly because she is still coming to terms with the relatively recent death of Violet, her partner of almost four decades.

The visits to Elle’s old friends also bring some unresolved agonies “bubbling up through the tar”, as Sam Elliott’s character evocatively puts it – though Weitz, who honed his craft on far broader stuff than this (About a Boy, American Dreamz, and co-directing American Pie), has a habit of spelling out in dialogue the kind of emotional processes his cast are frequently able to get across in a look.

An early scene in which Elle feuds with a coffee shop attendant (John Cho) is badly misjudged, and paints the character as a one-note comedy curmudgeon that’s grimly reminiscent of Fockers-period De Niro. It’s testament to Tomlin’s prowess as a performer, and also her plausible rapport with Garner (who looks uncannily like a teenage Elisabeth Moss), that the film recovers as quickly as it does. 

Grandma may not always know best, but it's nearly always funny and absorbing, and there are moments of emotional perspicacity to make you gulp.