Intruders: Flight of the Kestrel Book 1

Possible sabotage at a razor quartz mine gives Captain Joseph Darrow the final evidence he needs to prove that there is an unknown alien species stealing from sites across the galaxy. A man is killed at one of their raids, and his last word is 'butterfly'. What does it mean? Darrow's ship the Kestrel is sent to contact these 'Intruders', despite being small and ill-equipped for such a mission, and the allied species insist on sending representatives too, making it overcrowded. With them com...