Marissa was a librarian at the public library in Hawkins, Indiana. At one point she dated the police chief Jim Hopper. She briefly assisted him and Officer Powell in finding information about Hawkins National Laboratory.
At some point, Marissa dated Jim Hopper - however, this relationship disintegrated, with the two not being on friendly terms. According to Marissa, Hopper "wasted" her time, suggesting that he was non-committal to the relationship.
On November 9, 1983, Hopper and his deputy Powell entered the library, hoping to learn more about the nearby Hawkins National Laboratory. After a brief but tense altercation between Marissa and Hopper, she helped the two men find the information they needed.
On November 1, 1984, Dustin Henderson attempted to check out several books from the library. Marissa wouldn't allow him, as he had too many books checked out already. When Dustin was unsuccessful in convincing her to allow him to have the books, he distracted her and took them anyway.
|Season One appearances|
| ||Holly, Jolly|| |
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|Season Two appearances|
| ||The Pollywog|
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