You should watch:

Remember Me

This was episode number 5 of season 4.

The following characters appeared in this episode:

(voice) (uncredited) Enterprise Computer

Captain Jean-Luc Picard

Chief Miles O'Brien

Counselor Deanna Troi

Commander Wiliam T Riker

Doctor Beverly Crusher

Doctor Dalen Quaice

Ensign Wesley Crusher

Lieutenant Worf

Lt Commander Data

Lt Commander Geordi La Forge

The Traveler