“Fuhgeddaboudit” is episode fifteen of season two of Dark Angel.
Logan has asked Max to try and get a mob accountant to turn on his boss. The boss keeps his identity secret, and never goes out without a disguise, so no-one knows what he looks like. The accountant, the aptly-named Books, had almost turned on his boss before for Eyes Only, but backed out at the last minute.
Things are made rather more complex when another Manticore escapee gets involved. This is another of the non-combat ones, even though she does have physical enhancements. Instead, she’s PsyOps, and can mess with peoples’ minds (PsyOps as in psychic, not psychological), convincing them to do things and forgetting what they know.
Max forgets why she was looking for Books, and the other X5 also gets Alec to start cage fighting again.