Crey tasked you with finding out who the hero snooping around Grandville is. You broke into a Council base that had recently been attacked and stole the surveillance tapes which revealed the adversary to be none other than the Freedom Phalanx's speedster-Blaster, Synapse.
Crey's file on Synapse said that he could be bought out, if the price was right. You decided to use some gold doubloons that Arachnos has stored in order to fund the little buyout of Synapse. You put word out to meet with Synapse as soon as you got the doubloons. Once you got them, though, you found out your data was a little out of date. Synapse tried to take you down, but you prevailed, forcing him to use his Medicom to escape.
You found out that Synapse was being helped by the Scrapyarders, and so you decided to send him a little warning by taking down one of their warehouses. In the midst of the battle you overheard two Scrapyarders discussing Synapse's 'protection'. Taking down these 'yarders you found a data file that talked about a Crey demon-making program, which must be why Synapse is in the Rogue Isles to begin with.
This whole artificial demon thing intrigued you, so when Tavish sent you on a simple Malta mission, you blew it off and investigated the Crey facility in Grandville instead. Leaving no witnesses, you uncovered their Demon Seed program, hybriding Paragon Protectors with Demons. During your little escapade, you found out that Mynx followed Synapse from Paragon City. She attempted to stop you, but failed.
Mynx and Longbow were trying to convince Synapse to leave the Rogue Isles before he was in any more danger. You uncovered Mynx's location and decided to put the hurt on her to draw out Synapse. She was tough, but eventually went down. Synapse gets the message now.
While you were taking out Mynx, Synapse was stealing the Demon Seed data from Crey, and they hired you to get it back before Synapse could high-tail it out of the Rogue Isles. You succeeded in defeating him and Mynx before they could leave with the data, and Crey paid you handsomely for your efforts.