Setting up a wifi network with no internet connection
I am setting up a wifi network in a location with NO internet connection.
I have an Airport Express at the location, and my MacBookAir .
I have a Samsung SmartTV at the location, and would like to use it to watch the content on my laptop (both iTunes and items in the Movies folder), but can't figure out how to do it. I tried an AppleTV 3rd generation, but that won't work because it requires an internet connection to complete set up. I am not having any luck with Airplay or Screen Mirroring either. I tried a Thunderbolt/HDMI converter, and I can get the picture on the TV, but the sound comes through my laptop. This is annoying because the TV is hooked up to a decent sound system.
The TV has two HDMI ports, one for cable/sat and one for a DVD player (MHL&DVI). It also has an ethernet port and a USB port.
I would *very much* like to stream from my laptop to my TV, but if I can't do that, then I will settled for whatever cabled set up will get both the video and audio into the TV. Is there a streaming box that does not require internet?
Any suggestions very welcome, especially if they are in basic English, I am really bad at network lingo.
Thanks in advance!
MacBook Air (11-inch Mid 2013), OS X El Capitan (10.11.3)