There was no Halloween episode of Season 1. It ran from June to August 2010 and did not resume until January 2011.
Lucas and Hanna kissed in Pretty little liars in season 1 episode 12.
episode 13 season 1
There isn't a 5th Season Yet. There Still On season 3B but the Other half of The season 3B comes back on January 2013. But you can Watch The Halloween Special On October 23rd!
you find out in season 2 in the season finale :)
its called the first secret and its on the 2nd season
Wren was in season 1 episode 4 and then comes back in season 2 episode 2
Season 1 Episode 1 ( Pilot )
Season 2 episode 9 :)
Yes, but before season 3 starts there is going to be a Halloween special in October.
The last episode but there is more of A to come!
the computer
I would recommend watching season 2 episode 13, even though it is not a continuation of the last episode.It is the pretty little liars halloween special.It goes back to the halloween before Ali disappeared, and sort of shows how some of the issues in the other episodes start. The episode also shows the first A message ever sent, and kind of hints at and plays on who A is,but still leaves you guessing.