Like life, it starts so well, tragedy is inevitably in store, and afterward, life goes on again. Every episode of new Channel 4 import Six Feet Under - the latest black-comic drama from HBO and the brainchild of American Beauty screenwriter Alan Ball - begins with a little bit of gruesomely ordinary, piteously avoidable accidental death, just to get us in the proper frame of mind.

It is maverick US cable channel HBO that we have to thank for the acrid, spot-on media satire that was The Larry Sanders Show, the bloke-upsetting comedy Sex And The City and of course the world-beatingly fantastic The Sopranos. Hence, another HBO series, naturally enough, means another programme built around a fantastic ensemble cast – and another family business. This time, it’s not about taking people out: it’s about undertaking, at Fisher and Sons’ funeral home, and what a normal average family the Fishers are. There’s matriarch Ruth, who’d just about found the courage to fall in love outside her emotionally barren marriage, shortly before her husband did the infuriating trick of dying on her. There’s layabout thirtysomething favourite-son Nate, good-hearted but directionless; and his brother, dour, hyper-responsible funeral director and closet gay man David, who only ever appears wearing a black suit and tie and a pained expression. There’s David’s lover Keith, a cop, a comfortably "out" gay man and an all-around decent human being, who in his affable normality represents a huge step forward in the pop-culture normalisation of gay characters. There’s precocious teenage daughter Claire, whose fierce intelligence and all-too-pragmatic world view - not unlike her cinematic predecessor in the cool-female-roles stakes, Thora Birch’s character in American Beauty – gets her branded a freak and a loser (that, and the fact that her motor is a repainted hearse). Last but not least, there’s their recently-departed late father, Nathaniel Fisher Sr himself, who appears sporadically from beyond the grave to heckle, or bully, or otherwise comprehensively wreck the heads of the family he left messily behind.

If the premise and characters intrigue, it’s the understated performances and the scriptwriters’ eye for the tangled complexities of real human behaviour that will really impress. Characters are flawed, but in an erratic, human way; personal relationships are rare and difficult – either societally "amoral" but full of good intention, or beautiful but fundamentally unreliable. The spectres of bankruptcy, bereavement, and the characters’ own rudderlessness, their own individual terrified searches for whoever and whatever they’re supposed to be in this life, haunt them as surely as Fisher Sr does.

The only thing that’s certain, as Nate’s mistress tells him, is that "everything changes." This death game sounds a lot like life.

Six Feet Under is on Mondays at 11.05pm (Channel 4) with repeats on Wednesdays at 9pm and Sundays at 11pm (E4)