During a mulitplayer game with 4 players:

Player A used the Scholarly Plagiarist, commiting him to a story with investigation tokens that belonged to player B.

Player B did not choose to intercept.

Player C decides to intercept. However, Player C does not have any investigation tokens on that story card.

Player A wins. Does he then use the Scholarly Plagiarist's ability to take a token from Player B even thou player B chose not to intercept?

To help out the discussion, Scholarly Plagiarist reads:

" If you win an (I) struggle in which Scholarly Plagiarist is participating, instead of the normal struggle effects, move a success token from the opponent's side of the story to yours."

If, indeed, you win the Investigation struggle, then you move "the" opponent's success token. Clearly not written for multi-player. If it had read "an" opponent's, then no problem - the winner would taget any of the 3 opponents and move one of their success tokens.

I think I would probably treat it like that - "an opponent". But you are going to have to house-rule this, because the text on the card doesn't make sense in multiplayer.

If you tried to interpret is "the one player who chose to oppose you at stories", then if nobody defended there would be no token moved. I think that is less than satisfactory. Thus I would go for "an opponent" - pick one if you win the Investigation struggle.