Michael Nagy

BUFFY THE VAMPIRE SLAYERS3, E16

Doppelgangland

While casting a magic spell, Anya and Willow inadvertently summon Willow's evil double from an alternative universe.
FIREFLYS1, E9

Ariel

A Serenity crew member turns traitor to help the government catch fugitive siblings River and Simon, who has hired the crew to break into an Alliance hospital to steal medical supplies and to learn more about experiments done on his sister.
ALIASS4, E6

Nocturne

A hallucinogen causes Sydney to slowly lose contact with reality, and the team has to race against time to find an antidote before she becomes a danger to herself and them.