User blog comment:Barry19/TDA's 'The Islands of Death' synopsis and more Season 1 hints!/@comment-24825392-20141016180345/@comment-28119130-20141016180651

Somewhere between eps 1-7 there will be an new alien criminal, and episode 1 might have some new monsters.

For the arc... Well, it will be a pretty obvious arc, and halfway through the series the Doctor already notices it... But enough spoliers for now ;)