You should watch:

Unification: Part 1

This was episode number 7 of season 5.

The following characters appeared in this episode:

(uncredited) Ensign Jae

(voice) Enterprise Computer

Admiral Brackett

B'Ijik

Captain K'Vada

Captain Jean-Luc Picard

Counselor Deanna Troi

Commander Wiliam T Riker

Doctor Beverly Crusher

Jaron

Klim Dokachin

Lieutenant Worf

Lt Commander Data

Lt Commander Geordi La Forge

Perrin

Proconsul Neral

Sarek

Senator Pardek

Soup Woman

Spock