Star Trek: The Next Generation (1987)

S07E17 Masks

Stardate: 47615.2. The Enterprise undergoes a mysterious metamorphosis into a long-lost alien temple after Data uncovers an ancient archive brimming with knowledge about a bygone civilization. Upon accessing the archive, Data is overtaken by a multitude of distinct personalities, leading to unexpected consequences for the crew as they navigate the complexities of his shifting identities and the temple's strange influence.