Cody meets Krebbs, along with all of McLeach's other captured animals, when he is imprisoned and interrogated about Marahute's whereabouts. Krebbs, being an old and rather pessimistic koala, reflects on the hopelessness of the situation now that McLeach is trapping other humans. Cody assures them that there is a means of escape and Frank points out that they must get the keys, hanging by the door. Krebbs then sarcastically proposes that they start "packing their bags". Everyone pitches in to use a bunch of sticks and shoestrings to try and reach the keys, while Krebbs complains about Frank's incessant, excitable yelling and moaning. This attempt is unfortunately disrupted by Joanna. After Frank picks the lock and escapes his cell, he makes several attempts to reach the keys while Krebbs makes no secret of his lack of confidence in Frank. When Frank retrieves the keys and Cody escapes, McLeach appears and takes him away before he can free the others.
Although McLeach warns Cody that it is the last he'll ever see his new friends, he dies before being able to finish them off. Since Frank can pick the locks with his tail, it is possible that he freed them on his own and they made their escape.