Offred in the 1990 movie is named Kate, not June. In the book, Offred is always Offred; as chelseagirl says, June is only inferred.

When the book was first published, a lot of critics didn't believe Gilead could happen, either. They felt it seemed too over-the-top, even though everything Atwood mentions actually did occur at some point in history. Since the movie was released only 5 years later, it caught a lot of the same criticism too. It really took a generation for Atwood's genius to become apparent.

The book is definitely worth reading for comparison. The showrunners did a great job adapting the material. Without trying to spoil the book, there are significant differences between many of the book and TV versions of characters. The show, however, imo stays true to the book's central premise.

(Also, hello! Long time lurker here--just wanted to say I've read and enjoyed many of your reviews of various canons over the years. I'm glad to see you're reviewing The Handmaid's Tale too; s3 is going to start in June this year. I'm curious as to what you will think of s2.)