isKeyCharacterIn

Given a predicate that represents a relationship or action between entities, generate a one-sentence description explaining its meaning.  
# Instructions
Focus on describing the relationship, not the entities themselves. 
# Response Format
Begin the description with \' Indicates...\'

Predicate: isKeyCharacterIn

Indicates that an entity plays a central or primary role as a main or significant character within another entity, such as a story, game, or narrative work.