We’ve seen Richard Gere inhabit so many different roles — but rarely unsympathetic ones.

Robert Miller in Arbitrage is not bad to the bone like the sadistic cop i n Internal Affairs, but he’s hardly the dashing soldier whisking off a factory worker in Officer and a Gentleman or the knightly businessman courting a prostitute in Pretty Woman.

He’s just morally off, a slick New York banker who cheats on his wife ( Susan Sarandon) and his clients in the Nicholas Jarecki thriller, out Friday. But don’t worry, the man will pay for his misdeeds — in spades.

In the beginning of Arbitrage, Miller is living high on the hog, but things turn quickly. Viewers are left wondering for the next hour or so if his life is not going to merely spiral but crumble.

“You are never able to fully settle in,’’ Gere says. “A lot of my friends said they were completely drained after seeing it.”

The actor doesn’t see Robert as weak or evil. He sees something else.

“I think he’s full of himself,’’ says Gere, 63. “There’s an enormous amount of hubris and self-confidence.”

Despite the dual nature of the character, the Hollywood veteran found the role hard to resist.

“Every scene there was another twist that was unexpected. There aren’t that many movies being written that way now,’’ he says. “You’re always delighted when something fresh comes up.”

Another attraction was working with Tim Roth, who plays a busybody cop nosing into Miller’s personal life.

“He’s a terrific actor who made something out of a potentially [small] character but brought real life to it.”

When there’s comfort between actors, improv often takes place, the Philly native says.

“We were all pretty loose, but the script was really good,’’ he says. “Though you can always add an element.”

And you can’t overlook Sarandon, who also played Gere’s wife in 2004’s Shall We Dance.

“We’ve known each other a long time, and it works wells and comes through,’’ he says of the Oscar winner. “You have to kind of believe the relationship or the whole thing falls apart.”

They play a long married couple, sharing typical bedroom banter. Unbelievably, in one scene, Sarandon tells Robert not to forget to take his Lipitor. That’s Richard Gere you’re talking to!

Not to worry, even though he’s almost totally gray and ruggedly lined, Gere still looks stunningly handsome — and sexy.

Could be those elegant suits in which Robert preferred to do his dirty work.

“It’s not fun to dress up in a tie,’’ Gere admits, laughing. “But that’s the way the character would have dressed. I’m pretty sure it was Brioni that gave us those. This was a pretty small budget. I don’t think we could have afforded them!”

Madeleine Marr