There was a time, about 20 years ago, when a metaphysical query about a person whose life splits on some invisible cosmic axis and careens down multiple tracks would have been a wildly original idea for a movie. But the late Polish master Krzysztof Kieslowski came up with that premise for 1982's Blind Chance, and in recent years, it's been lifted twice to varying effect, once in the too-cute Gwyneth Paltrow vehicle Sliding Doors and again in Tom Tykwer's invigorating Run Lola Run. The wellspring of possibilities is nearly tapped out for Philippa Karmel's Me Myself I, a tepid and uninspired Australian comedy that ponders single and married life, but makes false assumptions about both. The appealing Rachel Griffiths, best known for starring opposite Emily Watson in Hilary And Jackie, plays a single, thirtysomething magazine writer whose loneliness leads her to the brink of suicide. One night, she finds a picture of an old boyfriend (David Roberts) and wistfully considers what might have happened had she accepted his marriage proposal and settled into suburban domesticity. She gets her answer when she's hit by a car driven by her doppelganger and, in a confusing flip-flop, assumes the role of wife and mother to three children. Her inexperience leads to some predictable hijinks in the kitchen and the bedroom (including an unfortunate diaphragm montage), but Me Myself I never takes its premise very far. Worse yet, it's got a disappointingly narrow idea of how marriage changes a woman. For example, the single Griffiths is a literate, prize-winning journalist with a voracious temperament; the married Griffiths is a bland personality who writes vacuous columns ("10 Steps To Keep Your Man") for a glossy magazine and considers Men Are From Mars, Women Are From Venus acceptable reading material. Me Myself I may be right to assume that marriage involves making sacrifices, but that doesn't mean the bride has to leave her frontal lobe at the altar.