The recently released Fallout 4 DLC, Far Harbor, features a quest that bears a remarkable similarity to a Fallout: New Vegas mod called Autumn Leaves.

The Far Harbor DLC for Fallout 4 received plenty of praise when it was released earlier this year, but now developer Bethesda is facing accusations of plagiarism. A quest included in the expansion called “Brain Dead” apparently bears some suspicious similarities to Autumn Leaves, a fan-made mod for New Vegas.

Autumn Leaves was developed over a period of four years, and centres around a perplexing whodunnit with six robots as the gallery of suspects. While it’s actually significantly longer that the Fallout 4 quest, the similarities in terms of plot, setting, and individual events are rather staggering.

Both Autumn Leaves and “Brain Dead” deal with the death of a Vault financier, who worked closely with Vault-Tec. Both use voice modulators as a major plot point, as both feature a cast of robots who could potentially have carried out the murder.

Both feature a scene where the protagonist discusses art with one of these robots, and both feature a scene where it’s possible to engage one of these machines romantically. All in all, there are plenty of resemblances between two quests set in the Fallout universe that were released less than a year apart.

far harbor autumn leaves

A comparison between environments in “Brain Dead” and Autumn Leaves.

However, Bethesda’s vice president of marketing Todd Hines doesn’t seem to see any evidence of foul play. Speaking to Gamespot, Hines stated that “any similarities between the two are a complete coincidence,” also speaking of the studio’s deep appreciation for the game’s lively modding community.

Guillaume Veer, the creator of Autumn Leaves, has responded to the comparison with calm rather than outrage. The modder argues that since his work takes plenty of inspiration from sci-fi literature and the Fallout franchise, there’s no great harm in the Fallout franchise taking some cues from his work.

That said, he would like to see Bethesda give some more credit to modders and their inventive output. Veer notes that people in his position are often trying to recommend themselves for a job in the industry, and being referenced in a game’s credits or similar could help make the process easier.

Unfortunately, it seems that Veer would have little opportunity to combat Bethesda on this issue, even if he had a desire to do so. The nature of modding means that any content created with the New Vegas engine likely belongs to the studio, regardless.

Fallout 4 is available now for PlayStation 4, Xbox One, and PC. Autumn Leaves is a free download that’s compatible with the PC version of Fallout: New Vegas.