This is the first book in a two book series.
The Abyss Beyond Dreams
The void. A near impenetrable region of space has long threatened to engulf the galaxy. Nigel Sheldon, co-inventor of wormhole technology, manages to force his way into the void in a purpose-built ship, but crash lands on the planet Bienvenido.
The planet is inhabited by descendants of those aboard colony ships lost hundreds of years before. But they are not alone on this world. Genocidal creatures known as Fallers continually attempt to infiltrate and destroy the human settlements.
Though the humans manage to hold their own against the Fallers, the government is corrupt and discontent threatens to become outright rebellion.
But as Nigel learns more about the Fallers, he discovers that they may provide a means by which the void can be destroyed entirely.