Teras Cassidy re-enacts an episode of the original Star Trek TV series in the place where it was filmed, Vasquez Rocks, near Los Angeles. Mr. Cassidy wants to expand his business beyond a small one-man outfit with two contract guides – one in the United States and one in Britain – and 10 to 12 tours a year. “I’m blessed with tons of support in the geek community from clients and people who really like what I’m doing,” Mr. Cassidy says.