Philip Roth has written one famous novel about masturbation and more than a few masturbatory novels about fame. With The Humbling, his 30th book, he’s added to the latter column, which is not to suggest that it’s a total waste of the reader’s time. But five full decades after the publication of his first collection of stories, Goodbye Columbus, Roth’s imaginative powers are in obvious decline. Though his mastery of the craft of prose remains strong, it can no longer consistently distract from his authorial sloth or redeem his prurient fixations.

The Humbling tells the story of Simon Axler, a world-famous stage and movie actor who, in his mid-sixties, suddenly and inexplicably loses the ability to act. (The theme of inexplicability is one to which we’ll return.) He falls into a deep depression, is abandoned by his wife, contemplates suicide, and signs himself in to a sanitarium, where he encounters – chastely – a young woman in even greater anguish than he. The young woman is not famous but, in a pointless digression that masquerades as a subplot, is on the cusp of becoming infamous.

Months later, Axler emerges from said sanitarium, resigned to the fact that his professional life is over, and secludes himself at his home in upstate New York. There, he is visited by Pegeen, the 40-year-old lesbian daughter of a pair of acting acquaintances; her heart has recently been broken by a former lover who decided to undergo gender-reassignment surgery. Axler’s encounter with Pegeen is decidedly unchaste, and she soon moves in with him, shuffling off both her previous orientation and its hoydenish trappings.

Axler and Pegeen are intermittently harassed by another of Pegeen’s former lovers, the statuesque red-headed dean who hired Pegeen to teach at Prescott, a nearby women’s college. Axler finds the jilted dean prowling around his property, and there is a hint that their confrontation might end in a ménage à trois. That doesn’t happen. But not to worry: Axler and Pegeen in short order pick up a drunk young woman at a local bar, and Roth has his inevitable threesome, complete with leather strap-on and cat o’ nine tails.

It would be difficult to imagine a more politically incorrect variation on the Pygmalion myth, with Axler molding Pegeen, by virtue of his mature sexuality, from the cold ivory of her lesbianism into the hot man-pleaser the gods always intended her to be. In the hands of a lesser writer, such a conceit would be unbearable. In Roth’s hands, it’s merely silly — and offset, to an extent, by the line-by-line pleasures of the prose. Roth seems constitutionally incapable of writing an unrhythmic line. Even that gift, however, is double-edged here, since all of his characters speak in a recognizable Rothian cadence, which, of course, is also the cadence of the third-person narrator. The effect is most noticeable in the minor characters, whose voices blur like the overly processed fare at the worst fast-food restaurants — where the burger, fries, shake, and Styrofoam cup all seem drawn from the same vat. Consider, for example, three of Axler’s fellow patients at the sanitarium who hold forth in rapid succession on the power of suicide:

Patient One: “You seem to yourself and to everyone around you paralyzed and wholly ineffectual and yet you can decide to commit the most difficult act there is. It’s exhilarating. It’s invigorating. It’s euphoric.”

Patient Two: “Yes, there’s a grim euphoria to it. Your life is falling apart, it has no center, and suicide is the one thing you can control.”

Patient Three: “The one thing that everyone wants to do with suicide is explain it. Explain it and judge it. It’s so appalling for the people that are left behind that there has to be a way of thinking about it.”