'The boys play it really cool when they meet celebrities, I don't - I just make a video for my sister!' Millie and the cast from Stranger Things chat to Grimmy about meeting famous fans of their hit TV show, from Robert Downey Jnr to the casts of Modern Family and Game of Thrones.

There's also a surprise in store for the cast as their no. 1 fan, Daniel Radcliffe leaves a message for them...