Episode Number: 1a
Season Episode Number: 1a
Voices: Chris Wiggins (Thor), Bernard Cowan (Narrator), Len Carlson (Loki), Peg Dixon (Jane Foster), (Nurse), (Male Bystander), (Female Bystander).
Plot: Loki is freed from his immortal prison and seeks revenge on the one who put him there - Thor!
Review (Warning! Spoilers!): The early days of Thor are found in Journey Into Mystery in the 60s until the title was officially renamed The Mighty Thor in 1966. This particular episode is taken from Journey Into Mystery #85 which is the first Silver Age appearance of Loki as well as Odin, Heimdall and a few others.
This chapter follow the story almost to the letter. There are two minor changes that are worth noting:
Loki makes a reference to Thor being his half-brother, but in the comics Loki refers to Thor as his ancient enemy. I'm not sure when the family connection was made between Thor and Loki, but it must have been sometime between JIM #85 and when this episode was produced.
The other change worth noting is the colours of the characters' costumes. For the majority of Loki's comic book career, he has been clad in yellow and green. In his first appearance he is dressed in brown, which they turn into purple in the next issue. It is this purple that they use in the series, and while I'm not used to seeing Loki looking so colourful, it is a nice look for him.
The other small colour change is making Thor's pant legs flesh-coloured. It makes him look like he's wearing briefs and really high boots, a fashion faux pas if I've ever seen one! This is an odd change as I don't recall Thor ever having a costume like that ever. I'm not sure why that change was made when they stick so closly to everything else.