Severus Snape is enjoying a drink in a Muggle pub when a stranger, whose face is covered, joins him. The stranger asks Snape about his story, which he then tells.
They appear in a forest at night, and James and Snape start dueling. However, Snape eventually becomes victorious, so Remus, Sirius, and (pressured by James) Peter join the fight, and they all produce the Fiendfyre spell, creating a big, four headed fire monster, with each head being their animal form. Snape disapparates to elsewhere in the forest, and Remus, Sirius and James do too, while Peter joins them on foot.
Using Legilimency, Snape predicts their next attack. However, the Marauders attack him at the same time, eventually having him cornered. Snape, remembering their bullying throughout the years, and Lily, rebounds the spells, applies the Cruciatus Curse to Sirius, and Sectumsempra to Remus. Snape attempts to curse Peter, but he takes on his rat form and escapes. Snape approaches James and attempts to kill him, but Lily apparates before him, demanding an explanation. Snape apologizes for calling her a Mudblood (seen in a flashback in Harry Potter and the Order of the Phoenix). Lily tells Snape that she will forgive him if he changes and stops being with Dark wizards, such as Bellatrix Lestrange. Lily disapparates with James, Remus, and Sirius.
Returning to the first scene at the pub, the stranger tells Snape that he knows how it feels to be subjugated and feared for one's talents. He then asks Snape to join his ranks. Snape demands to know who the stranger is. The stranger replies, "You-Know-Who."
After the success of the fan film, the Broad Strokes team starting working on a follow-up to Severus Snape and the Marauders, a 12-part audio drama called The Great Wizarding War written by Justin Zagri and Garrett Schweighauser . The audio adventure started in late 2019 with the same actors reprised their roles as the Marauders, Lily and Snape. The Great Wizarding War started the adventure just after the events of the fan film, and chronicles early days of the first war between the Order of the Phoenix and the Death Eaters. The final episodes were uploaded to YouTube on March 2, 2022.