Guardians of the Galaxy Part III debuted at theatres in May. The movie did quite well, earning $845 million, a certified hit for Marvel Studios. The last chapter was bittersweet as many of the beloved actors from the franchise will not be returning.

The movie recently hit Disney+, allowing for rewatches and for people who had not seen the film to check it out for the first time. This could trigger interest in the first appearances of some of the film's major characters. Here are some key books to keep an eye on or add to your collection.

Incredible Hulk #271 - First Rocket Raccoon

Guardians of the Galaxy 3 turns its focus on Rocket Raccoon. The devastating origin story shows viewers just why the anthropomorphic mammal was so angry all the time. The tale was sure to create many new Rocket fans and only endear him more to those collectors who were already behind him.

Technically, Rocket Raccoon's first appearance came in a magazine, Marvel Preview #7, issued in 1976. His first comic appearance, however, came in 1982's Incredible Hulk #271, which is much easier to find, even in high-end condition. A CGC 9.4 copy of the book will sell for between $250 and $300.

Avengers #257 - First Nebula 

Over the course of the Guardian's history in the MCU, Star-Lord, and Rocket have frequently clashed over the leadership of the group. In the latest installment of the film series, a new leader emerged; Nebula. Originally an enemy of the Guardians, the daughter of Thanos and sister of Gamora would soon become one of the Marvel Universe's greatest heroes.

Nebula was first created by Avengers writer Roger Stern and artist John Buscema. Her first appearance came in Avengers 257 where she battled against the group. The book has become more popular over the years and an issue in CGC 9.8 condition sells for slightly more than $200.

Marvel Premiere #1 - First Him as Adam Warlock 

While many faces were familiar in Guardians 3, one major character did make his first MCU appearance; Adam Warlock. The massively powered cosmic being was presented as young and confused, but he plays an incredibly important role in the film.

Adam first appeared in Fantastic Four 66, at that point, he was only known as him. Roy Thomas resurrected the character in 1972's Marvel Premiere 1, giving him the name Adam Warlock. The book sells briskly online, with CGC 9.0 copies going for around $400.

Strange Tales #180 - First Gamora 

Gamora appears in Guardians of the Galaxy 3, but it is a very different Gamora than we're used to. Peter Quill spends the majority of the film having difficulty coming to grips that this isn't the woman who loves him and Gamora is quite reluctant to go along on heroic missions.

Like Nebula, Gamora starts out as a villain who eventually comes to see the error of her ways. Her first appearance in comics comes in Strange Tales #180, where she sets off on a mission for Thanos. The issue sells for $350 in a CGC 9.4.

Thor #134 - First High Evolutionary 

Guardians of the Galaxy 3 introduced a new villain in The High Evolutionary and what a villain he was. The High Evolutionary stands as quite possibly the cruelest bad guy in the history of the MCU. Of course, there are plenty of collectors out there who like collecting evildoers.

This is the oldest recommended book on this list, it debuted in October of 1966. As a result, the issue can be quite expensive, so we are going to go with a lower grade. A CGC 8.0 copy of Thor 134 sells for between $450 and $550.

*Any perceived investment advice is that of the freelance blogger and does not represent advice on behalf of GoCollect.