iPad will not stop trying to download the same 27 movies

Go to iTunes and turn auto sync to off.

Disconnect your iPad from the computer.

In iTunes on PC/Mac, click Edit, Preferences or iTunes, Preferences

Under preferences, select Devices and then put a check mark next to "Prevent iPods.....from syncing automatically"

First of all, you might want to put your iPad into Airplane Mode to temporarily prevent these movies from being downloaded from the internet or over your wifi network. Use your iPad Control Center, or go to Settings -->Airplane Mode.

Check this setting on your iPad: General--> iTunes --> Wi-Fi Sync: if you have it turned on, and your iTunes on your computer is set to sync these movies, they will sync automatically over your wifi network with this setting ON.

Check this: Settings --> iTunes & App Store: Look at Automatic Downloads. If any of these are checked, new purchases (including free) made on other devices will be automatically downloaded. (I do not know if this also applies to Videos.)

Another setting that may come into play--- Check and see -- Do not turn it On, if it is Off:

if you have Settings --> iCloud --> Photos --> iCloud Photo Library turned ON, (not recommended if you still wish to sync photos and videos directly to your computer)... you can toggle a switch to store only lo-res copies of your photos on your device, saving local storage. Caution: I do not use this feature, therefore I do not know if it also applies to videos.