A composite turbine rotor blade that uses the high heat resistance capability of a ceramic material along with the high strength capability of a high strength metallic material. A main body or insert piece with a leading edge, a trailing edge and a blade tip is made from a single piece of CMC, Carbon/Carbon or high temperature resistant metallic material such as Columbium or Molybdenum. A pressure side wall piece and a suction side wall piece both made of the metallic material that is bonded together to sandwich in-between the insert piece. The insert piece includes a number of cross-over holes in which locking pins pass through from one of the two metallic pieces and form bond surfaces to bond the two metallic pieces together with the insert piece sandwiched in-between. The two metallic pieces each include a serpentine flow cooling circuit to provide cooling air flow form the metallic pieces.