Script: Fred Schiller & Reinhard Schwabenitzky
Los Angeles. Maggie (SANDRA PIRES), an up and coming musical star, she may be beautiful but other than that her only major talent is at elbowing people out on her way in her quest for fame. When her much more talented sister LISA (they look exactly alike) gets her first big break in show biz, Maggie moves in and steals the gig. How? That's simple, she just starts calling herself Lisa!

When the real LISA finds out that MAGGIE is back to her old tricks and that this time the evil twin is planning on flying to Austria with Lisa's boyfriend, TONY Kosminski, the composer, in order to steal Lisa's next big chance at a leading role (in Tony's new musical), and perhaps even to come onto Lisa's Tony, that's when the good twin finally looses her patience and goes berserk. 

MAGGIE and TONY are on their way to Europe so the only person LISA finds at home when she gets to Maggie's apartment is Maggie's German maid, KATHI Bluemlein (Elfi Eschke), whose only reason for being in Los Angeles is to make it in show business despite the fact that she's no longer in her prime. At first KATHI has no idea that MAGGIE isn't MAGGIE, but little by little she realizes that there's been a mix up and that it's not her boss but her boss' twin sister she's dealing with.

And as luck would have it, right at this time a lucrative TV offer comes through for Maggie. Now it's LISA's turn to pull a fast one. Virtually forced to do so by her sister's manager DAVID Greenbaum, a man head over heels in love with Maggie and an extremely jealous lover, she slips into the role of her sister and with the help of KATHI - who has for quite some time now been fed up with the way Maggie treats her- creates a commotion in the industry. She acts like a total bitch with the intent of spoiling Lisa's - that is Maggie's - reputation once and for all.

Meanwhile Maggie and Tony are touring Vienna and Salzburg. He is busy taking in the inspiring historical surroundings - his most recent musical is about Mozart's sister, Nannerl (and at the end of the movie it even wins an Oscar for the best musical film) - and she is busy trying to get Tony to notice her... To him she's suddenly a completely different person. He can't tell if the problem is her or him, all he knows is that something isn't right. 

Meanwhile back in Los Angeles KATHI, who suddenly sees her chance - albeit only a slim one - at scoring a role in a TV show, does her best to convince LISA not to let this chance slip away and to win the audition for the show. She argues that this would be the perfect opportunity for Lisa to show the world that she is a million times better than MAGGIE. Kathi does have a point, and besides there's something in it for her too.

Their plan works. The two women - LISA as singer and KATHI as comedian - get off to a good start and the show promises to be a smash hit.

But all of a sudden MAGGIE is back - frustrated and suffering from a sprained ankle. Europe has turned out to be a gigantic career flop, even her attempts to come on to the composer TONY failed miserably. And now - back in Los Angeles - she's in for another surprise: Maggie's beautiful apartment has been rented out (in the meantime LISA and KATHI have moved into a unaffordable expensive mansion - of course under Maggie's name and thus at her expense), she can't locate her manager DAVID, the guard won't let her into the TV studio - to put it simply, nothing's the way it used to be, it's as if she's landed on a strange planet.

It takes a few days but finally she finds them at the restaurant David usually hangs out at, all four of them DAVID, TONY, KATHI and of course LISA, sitting there peacefully having dinner together. Of course the fun's over now: two Lisas? Twins? Which one is which and which one was in Europe with Tony? Which one auditioned for the show? Confusion and chaos ensue.

The continuing battle between the two sisters over lover and career flares up again and reaches its peak on the day set for the live broadcast. Will the show have to be cancelled?

But Gordian knots do not pose a problem for good managers, and DAVID is a helluva good manager. And all's well that ends well: LISA and KATHI and their new show turn out to be a huge success; LISA gets her TONY back; KATHI gets the man of her dreams, DAVID (who has finally figured out how madly in love KATHI is with him - and he with her, too). And even that dirty rat, MAGGIE, ends up becoming a "star"...