Dance with the Devil

On patrol duty along the Klingon border, the USS McKenzie receives quite unexpectedly a Starfleet distress call.  It is intercepted as they near the perturbing region of the Paulson nebula, barely detectable, narrow-channeled and even heavily encrypted; as a distress signal, it simply makes no sense. All that can be deciphered from the weak, garbled, encoded message is something about an attack, heavy damage, adrift in the nebula and a name; USS First Legion, which is not registered anywhere in Starfleet records.

Still, it is a distress call and the Starfleet signal is genuine. General orders leaves no choice but to render immediate assistance, regardless of any previous orders or assignments. But right from the start, the McKenzie's small crew know they are going into more trouble than a simple rescue operation.