David Bowie died last year after a long and courageous battle with a terminal illness, officially.

Unofficially, you have to wonder about the effect on his health of hearing "Lust for Life," a song he cowrote with Iggy Pop, in a commercial for Carnival Cruise Lines. A song about "beating my brains with liquor and drugs" has been part of a sales pitch for unlimited access to the buffet and shuffleboard on the lido deck. It's probably the most egregious appropriation of a song outside of "City of New Orleans," used to pitch overnight laxatives (perhaps it was the line, "Halfway home, we'll be there by morning").

"Lust for Life" was put to far better use in the original Trainspotting, the 1996 U.K. smash about four young Scots who really did beat their brains with liquor and drugs, adapted by Danny Boyle from an Irvine Welsh novel that had become a sensation, a rallying cry for a generation rebelling against, as Brando once put it, "what have you got?"

There was Welsh's famous rant, crafted as a response to a British antidrug campaign called Choose Life. Think of it as their version of Just Say No.

As Welsh put it, by way of Ewan McGregor's character: "Choose a job. Choose a career. Choose a family. Choose a big television, choose washing machines, cars, compact-disc players, and electrical tin openers. … Choose sitting on that couch watching mind-numbing, spirit-crushing game shows. …"

At the time, I wondered what kind of spirit could be crushed by a game show, but that was before Hollywood Game Night.

Now the lads are back, in an unlikely sequel — three of the four young men were addicted to heroin, with its dismal survival rate. But they are all alive, and two have kicked the habit. Hard drugs, however, have given way to hard feelings. Mark Renton (McGregor), you may recall, made off with the proceeds of a drug deal, and vanished. In T2, he has returned, come back to Edinburgh for a fraught reunion with Sick Boy (Jonny Lee Miller), who's now called Simon, and who's running a blackmail business.

Spud (Ewen Bremner) is trying to beat heroin, and the fearsome psychopath Begbie (Robert Carlyle) has escaped prison and is sure to kill Mark if he finds him.

That's the plot, but not the point of T2, in which the middle-aged characters take stock of their misspent lives. The movie becomes — unexpectedly, and unhappily for those looking for another generational anthem — a rueful song about failure.

Sometimes, it's ruefully funny. There are blips of the old Trainspotting humor and energy (Mark and Simon at a Protestant bar, improvising an anti-Catholic song to save their skins), and snippets of the original movie itself, inserted into T2 to contrast the spent, failed fortysomethings with their younger selves.

T2, by invoking the original, has been accused of being a commercial for itself, but that sidesteps how bracingly brutal the movie is in assessing the shortcomings of its half-grown "men." Anger at Mark fades away, replaced by regret. The source of their bitterness isn't stolen money. It's an accounting of the riches they threw away — their youth, their obligations to people they loved, or should have.