You should watch:

Half a Life

This was episode number 22 of season 4.

The following characters appeared in this episode:

(uncredited) Ensign Kellogg
B'Tardat
Captain Jean-Luc Picard
Chief Miles O'Brien
Counselor Deanna Troi
Commander Wiliam T Riker
Dara
Doctor Beverly Crusher
Lieutenant Worf
Lt Commander Data
Lt Commander Geordi La Forge
Lwaxana Troi
Mr. Homn
Timicin