Hibernate not finding map property

So I am getting the exception:
org.hibernate.AnnotationException: mappedBy reference an unknown target entity property: se.mulander.cosmos.movies.model.Cast.starredIn in se.mulander.cosmos.movies.model.ExtendedMovie.cast

But I can’t really figure out why.
The two objects that I am going to map are:

@Entity
@Table(name = "cast")
@ApiModel(description = "A cast member that has been part of making the movie")
public class Cast
{
    @JsonIgnore
    @ManyToOne(fetch = FetchType.EAGER, cascade = {CascadeType.ALL})
    @JoinColumn(name = "movie_id")
    public ExtendedMovie starredIn;
}

and

@Entity
@Table(name = "extended_movie")
public class ExtendedMovie
{
    @OneToMany(cascade = {CascadeType.ALL}, mappedBy = "starredIn", orphanRemoval = true)
    @LazyCollection(LazyCollectionOption.FALSE)
    public List<Cast> cast = new ArrayList<>();
}

I have stripped them of some other properties, but in essence this is the relationship that is not working.

So what I don’t get is why it says that it is an unknown property, as the property is public and hibernate shouldn’t have any problems mapping it.

what is it that I am missing here?

Try something like:

ExtendedMovie :

@Entity
public class ExtendedMovie implements Serializable {
    private static final long serialVersionUID = 6771189878622264738L;
    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    private Long id;
    @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.EAGER, orphanRemoval = true)
    @JoinColumn(name = "cast_id", referencedColumnName = "id")
    private Set<Cast> cast;

    public Set<Cast> getCast() {
        return cast;
    }

    public void setCast(Set<Cast> cast) {
        this.cast= cast;
    }
}

Cast:

@Entity
@ApiModel(description = "A cast member that has been part of making the movie")
public class Cast implements Serializable {
    private static final long serialVersionUID = 6771189878622265738L;
    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    private Long id;
    //Remove extendedmovie from here
    //other property getter and setters here
}

This will establish a one-to-many relationship between ExtendedMovie and Cast.