TV The X-Files - Season 4 Episode 21 : Zero Sum The X-Files - Season 4 Episode 21 : Zero Sum 8.372/10 by 3394 users After a swarm of bees mysteriously kill a postal worker in an enclosed restroom, Assistant Director Skinner covers it up by destroying the evidence. In order to complete the task he poses as Agent Mulder, however his deception backfires. When Mulder finds out and confronts him, Skinner reveals that he is working for the Cigarette-Smoking Man in order to obtain a possible cure for Scully's cancer. Details Casts Posters Images Title The X-Files - Season 4 Episode 21 : Zero Sum Alternative Titles Arquivo X(1993), X档案, Akte X, Expediente X, X Files, Ανεξερεύνητες Υποθέσεις, X檔案, پرونده های مجهول, پروندههای مجهول, 엑스 파일, X-파일, 엑스파일, X 파일, X파일, Los Expedientes Secretos X, Секретні матеріали, The X-Files First Air Date 1993-09-10 Last Air Date 2018-03-21 Number of Episodes 218 Number of Seasons 11 Genres Mystery, Sci-Fi & Fantasy, Crime, Networks FOX, Casts David Duchovny, Gillian Anderson, Mitch Pileggi Plot Keywords , Fox Mulder David Duchovny Dana Scully Gillian Anderson Walter Skinner Mitch Pileggi Episodes List The X-Files Season 4 :Episode 1 Herrenvolk (2) Herrenvolk (2) 1996-10-04 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 2 Home Home 1996-10-11 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 3 Teliko Teliko 1996-10-18 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 4 Unruhe Unruhe 1996-10-27 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 5 The Field Where I Died The Field Where I Died 1996-11-03 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 6 Sanguinarium Sanguinarium 1996-11-10 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 7 Musings of a Cigarette Smoking Man Musings of a Cigarette Smoking Man 1996-11-17 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 8 Tunguska (1) Tunguska (1) 1996-11-24 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 9 Terma (2) Terma (2) 1996-12-01 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 10 Paper Hearts Paper Hearts 1996-12-15 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 11 El Mundo Gira El Mundo Gira 1997-01-12 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 12 Leonard Betts Leonard Betts 1997-01-26 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 13 Never Again Never Again 1997-02-02 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 14 Memento Mori Memento Mori 1997-02-09 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 15 Kaddish Kaddish 1997-02-16 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 16 Unrequited Unrequited 1997-02-23 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 17 Tempus Fugit (1) Tempus Fugit (1) 1997-03-16 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 18 Max (2) Max (2) 1997-03-23 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 19 Synchrony Synchrony 1997-04-13 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 20 Small Potatoes Small Potatoes 1997-04-20 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 21 Zero Sum Zero Sum 1997-04-27 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 22 Elegy Elegy 1997-05-04 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 23 Demons Demons 1997-05-11 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena.... The X-Files Season 4 :Episode 24 Gethsemane (1) Gethsemane (1) 1997-05-18 The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena....