Atlantis: Season 1, Episode 5

1 - 5:

After receiving a night-time message from outside the city, Ariadne calls on Jason and his friends to help her to find the sender. But leaving the city without raising the Queen's suspicions seems impossible - especially when they find out that the message was written by Therus, Ariadne's exiled brother. As Heptarian and the King's guards get closer to finding him, Ariadne must decide if her loyalties lie in Atlantis or with her royal sibling.