Well, I would start by creating a new forum category under Amc Tv Discussion.
This category could be Amc Tv News
Then you go to MyBB and install
this plugin,
http://mods.mybb.com/view/rss-feed-poster
There is a thread at MyBB forums about the RSS poster plugin,
http://community.mybb.com/thread-103173.html
However this might be related to a previous version found here,
http://mods.mybb.com/view/rss-to-post
If you experience some problem installing the plugin, you can refer to such thread to fix it or ask directly on that forum, but Keep in mind that the first Link posted above seems to be the more recent and may not cause any installation problem.
After installing this plugin, you will find an option to set it up inside your admin control panel. Scroll down to find it.
From there you can specify the forum where you want the updates to appear (your newly created suggestd forum) an also options to specify how many feeds must be displayed, and a field where you need to specify the feed URL.
I just visited AMC Tv blog and their RSS feeds are down. This could be the best source to post updates on their show, but not being available, the best suggestion is creating a Google Alert for AMC Tv and retrieve the feeds from there.
At Google go here
http://www.google.com/alerts
Fill out the relevant fields including in your query AMC Tv, plus your relevant interest (shows, news, etc.)
Sign in with a Google account and then select from inside your dashboard RSS, then you will be given with the relevant feed URL for your forum RSS poster.
P.S. PLEASE, make a backup of your database before making this install, just in case something could go wrong, but likely you will get things working fine