When Arkell and Dar first met there was no tension or danger. Which in and of itself was strange given two such dangerous beings. Rather, an instant bonding took place which has defied all scientific analysis for the ten years they have been partners. They communicated both telepathically and empathically. Regardless of distance, they 'felt' what the other felt. Words like loyalty, trust, understanding, even love were inadequate to express the strength and depth of that symbiotic bonding. From the day Arkell first saw Dar they 'became' one. And for the past ten years they had become a legend in the Federation...the penultimate fighting machine. They had never failed in a mission. Eventually, the mere threat to dispatch the 'Two That Are One' became sufficient negative incentive to precipitate immediate discussions and to end conflict.