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Symbiosis

This was episode number 21 of season 1.

The following characters appeared in this episode:

(as Judson Scott)Sobi

(uncredited)Margan

(as Kimberly Farr) Langor

Captain Jean-Luc Picard

Counselor Deanna Troi

Commander Wiliam T Riker

Doctor Beverly Crusher

Lieutenant Tasha Yar

Lieutenant Geordi La Forge

Lieutenant Worf

Lt Commander Data

Romas

T'Jon

Wesley Crusher