1. A method of joint generation of a mosaic of scenes, comprising: selecting by each of a plurality of users one of a plurality of characters which are imaged in a plurality of media content items; alternately selecting by said plurality of users a plurality of expression indications, each said expression indication is selected during another of a plurality of user interactions which are held alternately with said plurality of users using a plurality of client terminals; sequentially selecting a plurality of scenes which are extracted from said plurality of media content items, each said scene is selected in another of said plurality of user interactions according to a respective said expression indication and images a respective character from said plurality of characters; and automatically generating a scene mosaic which comprises said plurality of scenes.