Neil Patrick Harris is joining the growing cast for the upcoming four installment to the 'Matrix' series. Keanu Reeves and Carrie-Anne Moss have already announced they are reprising their roles in "Matrix 4' but NPH's role is yet unclear. The movie is expected to begin filming at the beginning of 2020 and no doubt expected to bring in big profits, with the first three films grossing $1.6 billion.