Ulysses is engaging in trade with a Kiliti vessel crossing the Desert. As the vessels conclude business and prepare to retract their moors, both ships are scanned by a large object. Consoles on Ulysses begin rapidly cycling through data; most flicker while a few overload- the ship's automated defense against intrusion sound yellow alert. The object, which appears to be a 400-meter-long carbon body, begins shutting down Ulysses' systems! It is a race against time to save some resources to keep life support functioning.
The Kiliti vessel is unaffected, but Ulysses has lost all but battery power and minimal computer function. It will take several hours to flush the Ulysses' computers of what appears to be a cascade virus.
Why was the ship attacked? Why are the Kiliti unaffected? The Ulysses mounts an investigation on the carbon body- a Von Neumann Probe of some kind. Meanwhile, the virus has reconfigured our subspace relay subroutines and is sending out some kind of a pulse signal. The increasingly irate (afraid?) Kiliti wish to retract their moorings but with power offline and four personnel trapped in the gang tubes, Ulysses is unable to do so.