TELEVISION - Jan. 7, 1993

‘R&S;’ Marathon: Fans of “The Ren & Stimpy Show” can catch all 13 episodes of the animated series--including the never-before-seen 13th episode--in a marathon screening coming up on MTV. The showcase begins Sunday at 10 p.m. with four back-to-back episodes, then continues Monday through Wednesday with three episodes back-to-back nightly starting at 10 p.m. The “world premiere” of “The Son of Stimpy,” the previously unseen episode, tops off the showings Wednesday at 11 p.m.