“Irresponsible” is the episode thirteen of season three of Stargate: Atlantis.
This episode sees the return of Lucius Lavin, who was previously seen in the season three episode, “Irresistible”. He claims that he is no longer using his potion to make people like him, and has apparently turned over a new leaf. The title of the episode would suggest otherwise.
He is now invincible because he has an Ancient shield. It turns out he is still a dubious character, but his actions result in Kolya and his Genii invading the village, looking for Sheppard and his team.
Lucius is definitely an irritating character, but he is probably intended to be so. Even if he does turn over a new leaf to a certain extent.
Another episode which is not part of the main Wraith plot. Unfortunately, it looks like it heralds the end of a one of the more interesting subsidiary plots.