Katie Holmes made her way out in New York City, on November 9, 2011. Credit: Fame Pictures

Tom Cruise has played a spy in four Mission: Impossible films, but in real life, Katie Holmes sure knows how to operate on the down-low.

A source tells the Los Angeles Times that the actress and fashion designer, 33, used a disposable cell phone -- "provided by a friend" -- to contact her lawyers and plot her divorce from Cruise, 50, in secret.

This stealth move, the LA Times reports, enabled Suri's mom to prepare her bombshell divorce, hiring three law firms in three states and filing without the detection of her superstar husband and his vigilant team.

However she pulled it off, it worked: By all accounts, a shocked Cruise did not see it coming when Holmes filed her papers June 28. By this past Monday July 9, the spouses of nearly six years had speedily settled the split with their lawyers, with Holmes nabbing primary legal custody of Suri.

"She pulled it off brilliantly," an insider told Us Weekly. "This was all played so well."