Bonanza: Under Attack

Bonanza Under Attack is a 1995 TVmovie sequel to the 19591973 television series Bonanza and television films Bonanza The Next Generation 1988 and Bonanza The Return 1993. The movie was directed by Mark Tinker and features noted character actors Ben Johnson, Jack Elam, Dennis Farina, and Richard Roundtree, as well as Leonard Nimoy.

Source: Wikipedia