Houston, we have quite a few problems

Busted, criticised, ridiculed: it hasn't been the best of years for Whitney Houston. An odd time, then, for her to launch a high-profile comeback.

Next Monday, the US Network NBC will screen an extended music special, celebrating the 25th anniversary of Arista Records. The label's current roll-call is impressive - among the show's stars will be Carlos Santana, rap star Puff Daddy, soul diva Toni Braxton and Sixties legend Aretha Franklin.

But most eyes will be on Whitney Houston, stumbling hesitantly on to the promotional treadmill just as her Greatest Hits collection is released. She sings a medley of those gleaming hits - "Saving All My Love For You", "The Greatest Love Of All", "I Will Always Love You" - but that isn't the reason the viewing public will be watching her spot so closely.

In the last few months, Houston has had a rather rum time of it. In January, she was found in possession of cannabis at a Hawaiian airport, though she managed to scarper back to the US mainland before the police arrived. In March, she failed to appear for a performance at this year's Oscars. Her label blamed a sore throat, but inside whispers claim that the show's musical directors, Burt Bacharach and Don Was, told her to go home after a run of odd behaviour.

The Arista special, then, offered Houston a chance to clear the air. And though her performance, taped last Monday, is reportedly up to scratch, her demeanour was as off-beam as usual. "At one point," said Entertainment Weekly, "she stumbles centre stage - and they show it!" To make things worse, three days after the recording came an all-too familiar scenario: her husband, accident-prone R&B singer Bobby Brown, was picked up by police on a warrant issued when his probation officer reported that cocaine had been found in his urine. It can't be easy being Whitney Houston.

The Greatest Hits, far from being some valedictory high-water mark, has the aura of a record issued to pull her back to her rightful place after a run of commercial underachievement and personal crisis. And if that sounds cynical, many in the US see the album as a last-ditch attempt by Arista to squeeze some big money out of their most unpredictable asset. In the short term, the record's release has had the rather unwelcome effect of pulling its author back into the limelight when that may be the last thing she needs.

The Oscars apart, her PR people have just recovered from a particularly unflattering bit of coverage in the American women's magazine Jane - a cover story in which showbiz etiquette was cruelly suspended and Houston's bad behaviour formed the glue of the story. She gave the interviewer a mere 26 minutes and turned up four hours late for the picture shoot, claiming she had been to the dentist. "When Whitney arrived," runs the piece, "she was extremely unfocused, had trouble keeping her eyes open and kept singing and playing an imaginary piano on the table. I guess laughing gas can do that to you."

To cap it all, when asked about a diamond bracelet she wore to the shoot, her reply - "I asked this Jew guy on Diamond Row in New York to make it" - was couched in a bald racial vocabulary that hardly became a million-selling icon.

Unfortunately, Whitney's travails this year are not some sudden, aberrant turn for the worse. Her problems date back to the mid-1990s, when her marriage to Brown began to hurl forth all manner of regrettable gossip. They were hitched in 1992, and had a daughter, Bobbi Kristina, in 1993. By 1997, however, any impression of domestic bliss was long gone. In July of that year, while holidaying with Brown on the island of Capri, Houston suffered a cut face. In June 1998, rumours that the couple were splitting reached fever pitch. At around the same time, Brown was arrested for sexual battery after slapping a teenager's backside. The charge was later dropped, though he has hardly been on the straight and narrow ever since. His subsequent history is littered with arrests for drink-driving and brawling - one fracas took place in the inappropriate environs of Disney World. In September 1998, he was jailed in Florida for driving under the influence of alcohol - in addition to being fined $500, placed in a residential substance abuse treatment centre, ordered to undergo random drug and alcohol testing, and sentenced to 100 hours of community service.

His biggest hit remains a song called "My Prerogative", but his wayward temperament was no longer much of a defence. In the meantime, Houston's career was stalling. 1998's My Love Is Your Love was her first proper studio album for eight years, and entered the US charts at No 13. The story of the album's creation only fuelled the talk of a career crisis: a Greatest Hits had been mooted for the tail-end of 1998, Houston duly entered the studio to record a handful of top-up tracks, but decided to turn the sessions into a new record. It was recorded in six weeks - small wonder it sounded patchy.

In the wake of the record's release, observers reckoned Houston had been eclipsed by a new generation of black female stars: Lauryn Hill, Missy 'Misdemeanour' Elliott, Mary J Blige. Only furthering the impression of artistic decline, she flew into Britain at the tail end of 1999 for a run of concerts that saw some strange scenes - Houston taking the stage late, happily describing the rigours of the performance, and making giggly allusions to rumours of her drug use. Her show at Birmingham NEC was the oddest: newspaper reports were united by a sense of amused bafflement.

All that said, it was this phase of her career that threw up arguably her best single ever: a composition that left behind the trilling schmaltz that had too often marked her progress, and brought genuine innovation into the mainstream. "It's Not Right, But It's OK" was a subtly avant-garde piece that had even the most snobbish critics in raptures.

If Houston frequently seems doomed, that she can still make music as good as this is a convincing counter-argument. Quite what happened to her film career, however, remains a mystery. The Bodyguard, the anodyne showbiz flick from 1992, grossed $400m. Waiting To Exhale, acclaimed as a pioneering examination of the female African-American experience, did her dramatic prospects no harm at all - but since 1996's The Preacher's Wife underperformed, Hollywood has been totally untroubled by her presence.

But that may be about to change. Jane reports that Houston and Will Smith have been working on a film script for almost a year. The movie, Diva, is reportedly about "a prima donna in Paris who gets involved in smuggling". As is increasingly the case in the world of Whitney, you couldn't make it up.