He joins or supports Anakin Skywalker/Darth Vader , Obi-Wan Kenobi (portrayed by Alec Guinness and Ewan McGregor ), and R2-D2′s droid companion C-3PO (played by Anthony Daniels ) in various points in the saga. R2-D2 was played by Kenny Baker . The original R2-D2 was designed by John Stears and specially created