On Monday, Arnold Schwarzenegger, the former Republican governor of the most populous state in the nation, paid a visit to Manhattan, and it was easy to wonder what might have been, if not for California's fiscal ruin, the love child, and the inconvenient matter of the Constitution's prohibition on foreign-born presidential candidates.

But as his old colleague Mitt Romney meticulously prepared debate zingers, a humbled Schwarzenegger was doing the publicity rounds for his new autobiography, Total Recall. Perhaps in need of a sympathetic audience, after confessing manifold infidelities on "Good Morning America," he tweeted out an announcement: a "surprise" book signing at the Soho bookstore McNally Jackson.

I arrived at the appointed time to find the sidewalk outside the bookstore crammed with news cameras, random gawkers and Arnold enthusiasts, lined up with hardcovers behind a red velvet rope. There was no sign of Schwarzenegger, though, so I squeezed in the door and went inside, where a few bemused patrons and bookstore employees went about their daily business, unimpeded by his security detail. I bought a magazine and a bowl of vegetable soup and sat down in the bookstore cafe, where I was able to watch the scene unfold.

Shortly before Schwarzenegger's arrival, a man wearing an earpiece appeared in the bookstore, and announced that everyone was to clear away from the front area of the store—no loitering around the table for new releases and the magazine racks. For the most part, people complied, although one frazzle-haired reader remained sitting, studiously unmoved, in the adjacent travel section as Schwarzenegger swaggered to the table that had been set up for his book signing.

The author, orangey-skinned, wore a dark suit, and he was all business. There was no reading from the book, and no speech. He had tweeted that it was his first-ever book signing, but one clerk marveled, appreciatively, that he showed a pro's touch for keeping the line moving.

It was not hard to tell the McNally Jackson regulars from the Total Recall readers. The latter group included two musclebound guys in tight t-shirts that read "Fitocracy," a notable number of attractive young women, and accented tourists of many nations.

"I just talked to Arnold Schwarzenegger," one shouted giddily into his cell phone as he made his way out of the store.

One couple sat down next to me at a cafe table, comparing digital photos and observations about the experience. One thing they noted was that Schwarzenegger seemed to start off each interaction with a comment on his interlocutor's physical fitness; another thing was that the whole interaction was over in a flash.

"I was too nervous to get a good picture," the woman told her friend.

I weighed the possibility of a quote against the $35 list price, and settled on thrift.

I announced myself to the Schwarzenegger retinue. A blonde woman, introduced as the author's publicity agent, turned down a request for an interview.

"This is for the fans," she said, firmly.

Outside, the TV reporters, restless, plied Schwarzenegger's devotees with questions about their feelings regarding his indiscretions. The mood was forgiving. A rotund fellow—clearly not a member of the Fitocracy—introduced himself to the TV reporters as a contributor the Schwarzenegger-devoted website TheArnoldFans.com.

"He's still a hero," the fan-club guy told "Inside Edition," and then he did a well-practiced impression of that famous Teutonic growl. Afterward, the Fox 5 crew grabbed him, and he repeated the impression all over again.

No one brought up Romney, or Republican politics. The Schwarzenegger who told the 2004 G.O.P. convention, "Don't be economic girlie men!" has been all but invisible in this presidential campaign—the role of governor turned out to be one of the movie star's more forgettable parts.

When it was time for Schwarzenegger to leave, his ride—a black Chevy S.U.V. equipped with red and blue police lights, for some reason—roared to life. Remotely, someone clicked the doors unlocked. The guy with the earpiece brusquely cleared a path. The crowd on the sidewalk outside the bookstore swelled with curious onlookers, wondering who was about to emerge.

"What?" said a bearded man, with many missing teeth, when he learned that the dignitary was none other than Schwarzenegger. "Get outta here! He can write?"