You should watch:

Galaxy's Child

This was episode number 16 of season 4.

The following characters appeared in this episode:

(voice) (uncredited) Enterprise Computer

Captain Jean-Luc Picard

Counselor Deanna Troi

Commander Wiliam T Riker

Doctor Beverly Crusher

Dr Leah Brahms

Ensign Sariel Rager

Ensign Pavlik

Guinan

Lieutenant Worf

Lt Commander Data

Lt Commander Geordi La Forge

Transporter Technician Hubbell