One Actor in Two Roles & Film Body Doubles

All film & TV examples are without sound and for educational purposes only (FAIR USE). My own films can have sound. There is an easy way to make one actor play more than one role in the same scene. Newer visual effects can be more advanced, but it's not that difficult to do, with the right planning. Scene list below: 00:00 - intro 00:48 - body doubles 01:44 - OTS shots (over the shoulder) 02:20 - a common element 02:45 - matching eyelines 03:09 - different hair, props, wardrobe, etc 03:37 - reaction shots 04:18 - shoot one character at a time 05:35 - notable examples in film & TV