Joel is captured while acting as a spy in the village. He had been posing as a fish monger, selling fish to the kitchen slaves of the wealthy and gathering intelligence by listening to their gossip. It is through Joel's spying that Rosh learns the identity of the wealthy citizens attending a banquet thrown by Herod for some visiting Romans, all of whose houses are robbed. Joel grows more and more sure of his value as a spy and perhaps becomes too sure of himself.

In chapter 18, we learn that Joel has been captured by the Romans after a visit to the centurion's kitchen. It's not clear what the Romans know about his activity, but the implication is that some of the kitchen slaves talked after being tortured. Joel is arrested and taken to be a galley slave. Daniel appeals to Rosh for help in rescuing Joel, but Rosh refuses to help. Instead, Daniel gathers those that are loyal to him and makes a plan for rescuing Joel by intercepting the detachment of soldiers transporting prisoners to the sea.

Daniel's attack succeeds, but not because of him. Samson, who had stayed behind with Rosh, suddenly appears to help with the attack. Samson rolls a giant boulder on the Roman soldiers guarding the prisoners and throws Daniel and Joel to safety before being taken by the Romans.