the devil dark william shatners favorite episode also one favorite episodes program pure star trek deals one series main themes respect life forms think one could get clearer example one shows interesting ideas episode kirk crew confront monster killing miners distant planet story excuse explore right humans destroy creatures vital part environment todays concerns environmental causes make show relevant ever before extremely well written performed gusto beloved cast one memorable sequence involves spock joining mind monster plenty tension spock kirk they want solve problem using different methods adds fun shatner leonard nimoy best work here