RICHARD CURTIS’S Love Actually once again confirms that the writer and director is constitutionally incapable of deviating from his feel-good formula and upbeat obsessions. But formally he has stretched his creativity by using the structure of the multiple story line.

Looked at cynically, the multiplot structure of Love Actually is just a way of upping the happy-ending quotient. Why settle for one tearful, smiling hugfest, when you can cram in eight of the things? And why settle for one or two stars, when you can cram in two dozen, not including supermodel cameos.

The all-star cast is the studio’s double-edged sword. In the right vehicle it creates glamour and allure and has been doing so since Grand Hotel, The Great Escape, The Towering Inferno, etc. In the wrong one, the whole overburdened craft topples and sinks. Look no further than Bonfire of the Vanities, a confluence of tales all reducing its affable star cast to scheming grubby scum in the interests of haughty satire.

Love Actually obviously concentrates on the nobler impulses in its star cast. Along with its connecting theme, Curtis has woven in a few tangential or coincidental connections to his many stories. Some characters turn out to be related, others are neighbours; half the cast seem to have kids or teach at the same school, while the other half wind up bumping past each other at the airport as they greet their respective loved ones.

The effect is a paradox — plotting that is both random and symmetrical. The parallel structure with mild overlaps tacitly encourages the viewer to make comparisons and seek a deeper pattern. If the pattern turns out to be trite wish-fulfilment for any swain who makes it to the arrivals lounge, then clearly the potential of the form has not been realised.

With more conventional films multiple story lines are just plot lines that inexorably converge for a grand finale. The pattern quickly emerges — an inverted telescoping that will bring all the threads into collision. Despite not merging its plot lines so starkly, Love Actually can’t quite bring itself to embrace the more sophisticated resonance offered by multiple storytelling either. Curtis has cited Robert Altman, the director most linked with the form, as an influence — albeit jokingly — and he is clearly an admirer of Woody Allen with his spluttering witty romantic heroes and recurring Valentines to his home city.

Allen moved into multiple plots in the 1980s with A Midsummer Night’s Sex Comedy, his light spin on Bergman’s Smiles of a Summer Night, and Radio Days, his nostalgic compendium of his Brooklyn childhood. In Radio Days the linking device to the stories was obviously the wireless, but tucked into the comedy and unabashedly rose-tinted tone was some subtle social commentary. All the stories involved some area of social prejudice — interracial dating, homophobia, class, politics, religion. The poignant finale, on New Year’s Eve on the roof of the radio studio, saw the revellers wondering if anyone will remember them.

The festive gathering is a useful endstop for multiple stories. (Love Actually uses Christmas.) Apart from getting otherwise unconnected characters together in one place, the occasion lends itself to taking stock and cementing relationships. In Hannah and her Sisters Allen used Thanksgiving dinners to open and close his Chekovian roundelay of frustrated desire and sibling rivalry. He also started using multiple voiceovers, which encourages the viewer to understand each character’s point of view, however unethical their behaviour.

If the multiplot character comedy often feels like an inherently humanistic genre, it could well be down to the maxim uttered in Jean Renoir’s 1939 comedy Rules of the Game: “Everyone has his reasons.” Renoir’s bittersweet film was a country-house-weekend comedy — a favourite setting for cathartic multiple gatherings (see Gosford Park) because it offers the additional vertical dimension of master and servants.

All the stories in Rules of the Game are based on love, but in the airy French manner: infidelity is inexcusable only if one is cuckolding one’s host. D. W. Griffith had no such restraint. Intolerance, made in 1916, intercuts between four stories across four ages, from Babylonian to modern times, to illustrate its title theme with melodramatic gusto. With no temporal or geographical unity to link them, the only way these four stories can converge is thematically. But Griffith’s mastery of intercutting allowed the four stories to converge stylistically too. He sped up the editing as the four stories reached their peak to exhilarating effect.

It is amazing how patient audiences will be with separate story lines. Such is the conditioning of dramatic viewing that we just trust that a connection will be revealed. The Hours used three story lines set in three separate eras and waited right to the end before unveiling all their connections. Having only three stories to cut between makes a big difference in narrative momentum.

Multiple plot lines offer scope at the expense of depth. Robert Altman has used the most in one film: 24 interwoven stories in his 1975 “mosaic” of country singing aspirants, Nashville. The only way he found to yoke all these stories together was by adding a mid-concert assassination to the finale — a death ex machina, for want of a better phrase. Altman also created a political van that toured the city raining campaign hype on the characters as a way of keeping his thematic plates spinning.

In Short Cuts, he wove together Raymond Carver’s discrete short stories by setting them all in Los Angeles. The political van became a series of pesticide-spraying helicopters buzzing overhead. The death ex machina became an earthquake. The only deeper pattern revealed there was the San Andreas fault.

All-star casts

Pulp Fiction John Travolta, Samuel L. Jackson, Bruce Willis, Uma Thurman, Tim Roth, Harvey Keitel, Steve Buscemi

The Player Tim Robbins, Greta Scacchi, Whoopi Goldberg, Richard E. Grant, John Cusack, Jeff Goldblum, Anjelica Huston, Jack Lemmon, Burt Reynolds, Bruce Willis, Julia Roberts, Patrick Swayze

A Bridge Too Far Dirk Bogarde, James Caan, Michael Caine, Sean Connery, Edward Fox, Gene Hackman, Anthony Hopkins, Ryan O’Neal, Laurence Olivier, Robert Redford

The Towering Inferno Steve McQueen, Paul Newman, William Holden, Faye Dunaway, Richard Chamberlain, O.J. Simpson

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