"Gin" is an insurance investigator, "Mac" is an international art thief who likes a challenge. A priceless Rembrandt is stolen from an office: Gin thinks Mac is the thief, so she is sent to investigate him.
She tries to entrap him with a proposition, to help him steal a Chinese mask from a well-guarded palace. They travel to Scotland, and plan the complicated theft.
Just after they complete it, Mac accuses Gin of planning to sell the mask, and turn him in. Gin tells him she's planned an even bigger job, and persuades him to help her rob $8 billion from the International Clearance Bank, in the Petronas Towers in Kuala Lumpur.
The plan works, but they set off all the alarms, and narrowly escape. The next morning, Mac nearly hands Gin to the FBI, but has another plan to let her go, as he's getting old and she's got her life ahead of her.
Together, they then decide on a third job.