R2-D2 is lost during a fierce space battle -- and Anakin must find him before the Separatists discover the Jedi military secrets locked in his memory banks.

Ryloth, home world of the Twi'lek people, has been subjected to military occupation by the droid army of the Separatists, and surrounded by a blockade of Trade Federation battleships. While launching a surprise attack against the blockade, Ahsoka disobeys Anakin's orders and ends up losing most of her squadron. Even though she's emotionally rocked by this failure, Anakin helps her learn to persevere, placing her in charge of another risky attack.

Anakin and Ahsoka travel to the planet Devaron in pursuit of Cad Bane, who has stolen a Jedi holocron. Bane has captured Jedi Master Bolla Ropal, keeper of the Kyber crystal, which will reveal data on every known Force-sensitive child in the galaxy when combined with the holocron. Failing to force Ropal to open the holocron, Bane needs another Jedi. Capturing Ahsoka, the bounty hunter forces Anakin to open the holocron to save his Padawan. The holocron's secrets revealed, Bane attempts an escape, but appears to be killed by a clone. Anakin, however, still senses Bane's presence in the Force...