E-mail is titled "See what you're missing with these hidden gem channels"
From sender "firstname.lastname@example.org"
About two-thirds of the way down on the message there is a Vudu logo with the text:
"Get a $5 movie credit. Here's a special treat: this week only, get a free credit toward a rental from VUDU"
followed by a unique code.
Redeem code at Vudu: https://my.vudu.com/redeem.html?pn=generic
Code expires 1/28/2018.
Best of luck!
Update: Vudu is having a 50 cent movie rental sale... Great use for your credits! See this thread: