S02E19: Doppelgänger
The team investigates a missing woman's boyfriend, with whom she lived. However, they determine that he has a twin brother and quickly turn their attention to him.
Previous Episode 
Season 1
Pilot
S1E1 / 26 Sep 2002
Birthday Boy
S1E2 / 03 Oct 2002He Saw, She Saw
S1E3 / 10 Oct 2002Between the Cracks
S1E4 / 17 Oct 2002
Suspect
S1E5 / 24 Oct 2002Silent Partner
S1E6 / 31 Oct 2002Snatch Back
S1E7 / 07 Nov 2002Little Big Man
S1E8 / 14 Nov 2002
In Extremis
S1E9 / 21 Nov 2002Midnight Sun
S1E10 / 12 Dec 2002Maple Street
S1E11 / 09 Jan 2003
Underground Railroad
S1E12 / 16 Jan 2003
Hang On to Me
S1E13 / 30 Jan 2003The Friendly Skies
S1E14 / 06 Feb 2003
There Goes the Bride
S1E15 / 20 Feb 2003
Clare de Lune
S1E16 / 27 Feb 2003Kam Li
S1E17 / 13 Mar 2003The Source
S1E18 / 03 Apr 2003Victory for Humanity
S1E19 / 10 Apr 2003
No Mas
S1E20 / 24 Apr 2003Are You Now Or Have You Ever Been?
S1E21 / 01 May 2003
Fall Out (1)
S1E22 / 08 May 2003Fall Out (2)
S1E23 / 15 May 2003
Season 2
The Bus
S2E1 / 25 Sep 2003Revelations
S2E2 / 02 Oct 2003Confidence
S2E3 / 09 Oct 2003Prodigy
S2E4 / 23 Oct 2003Copycat
S2E5 / 30 Oct 2003Sons and Daughters
S2E6 / 06 Nov 2003A Tree Falls
S2E7 / 13 Nov 2003Trip Box
S2E8 / 20 Nov 2003Moving On
S2E9 / 11 Dec 2003Coming Home
S2E10 / 18 Dec 2003Exposure
S2E11 / 08 Jan 2004Hawks and Handsaws
S2E12 / 15 Jan 2004Life Rules
S2E13 / 29 Jan 2004The Line
S2E14 / 05 Feb 2004
Wannabe
S2E15 / 12 Feb 2004Risen
S2E16 / 19 Feb 2004
Gung Ho
S2E17 / 26 Feb 2004Legacy
S2E18 / 11 Mar 2004Doppelgänger
S2E19 / 01 Apr 2004Shadows
S2E20 / 15 Apr 2004Two Families
S2E21 / 29 Apr 2004The Season
S2E22 / 06 May 2004Lost and Found
S2E23 / 13 May 2004Bait
S2E24 / 20 May 2004
Season 3
In the Dark
S3E1 / 23 Sep 2004Thou Shalt Not
S3E2 / 07 Oct 2004Light Years
S3E3 / 14 Oct 2004Upstairs Downstairs
S3E4 / 21 Oct 2004American Goddess
S3E5 / 28 Oct 2004Nickel and Dimed (1)
S3E6 / 04 Nov 2004Nickel and Dimed (2)
S3E7 / 11 Nov 2004
Doppelgänger: Part 2
S3E8 / 18 Nov 2004Trials
S3E9 / 25 Nov 2004Malone v. Malone
S3E10 / 09 Dec 20044.0
S3E11 / 06 Jan 2005Penitence
S3E12 / 13 Jan 2005Volcano
S3E13 / 03 Feb 2005Neither Rain Nor Sleet
S3E14 / 10 Feb 2005Party Girl
S3E15 / 17 Feb 2005
Manhunt
S3E16 / 24 Feb 2005Lone Star
S3E17 / 10 Mar 2005Transitions
S3E18 / 31 Mar 2005Second Sight
S3E19 / 14 Apr 2005The Bogie Man
S3E20 / 04 May 2005Off the Tracks
S3E21 / 05 May 2005John Michaels
S3E22 / 12 May 2005Endgame
S3E23 / 19 May 2005
Season 4
Showdown
S4E1 / 29 Sep 2005Safe
S4E2 / 06 Oct 2005From the Ashes
S4E3 / 13 Oct 2005Lost Time
S4E4 / 20 Oct 2005Honor Bound
S4E5 / 27 Oct 2005Viuda Negra
S4E6 / 03 Nov 2005The Innocents
S4E7 / 10 Nov 2005A Day in the Life
S4E8 / 17 Nov 2005Freefall
S4E9 / 24 Nov 2005When Darkness Falls
S4E10 / 08 Dec 2005Blood Out
S4E11 / 05 Jan 2006Patient X
S4E12 / 19 Jan 2006Rage
S4E13 / 26 Jan 2006Odds or Evens
S4E14 / 02 Feb 2006The Stranger
S4E15 / 09 Feb 2006The Little Things
S4E16 / 02 Mar 2006Check Your Head
S4E17 / 09 Mar 2006The Road Home
S4E18 / 30 Mar 2006Expectations
S4E19 / 13 Apr 2006More Than This
S4E20 / 20 Apr 2006Shattered
S4E21 / 27 Apr 2006Requiem
S4E22 / 04 May 2006White Balance
S4E23 / 11 May 2006Crossroads
S4E24 / 18 May 2006
Season 5
Stolen
S5E1 / 24 Sep 2006Candy
S5E2 / 01 Oct 2006911
S5E3 / 08 Oct 2006All for One
S5E4 / 15 Oct 2006The Damage Done
S5E5 / 22 Oct 2006The Calm Before
S5E6 / 29 Oct 2006All the Sinners, Saints
S5E7 / 05 Nov 2006Win Today
S5E8 / 12 Nov 2006Watch Over Me
S5E9 / 19 Nov 2006The Thing with Feathers
S5E10 / 03 Dec 2006Fade-Away
S5E11 / 10 Dec 2006Tail Spin
S5E12 / 07 Jan 2007Eating Away
S5E13 / 14 Jan 2007Primed
S5E14 / 21 Jan 2007Desert Springs
S5E15 / 18 Feb 2007Without You
S5E16 / 04 Mar 2007Deep Water
S5E17 / 11 Mar 2007Connections
S5E18 / 18 Mar 2007At Rest
S5E19 / 25 Mar 2007Skin Deep
S5E20 / 08 Apr 2007Crash and Burn
S5E21 / 15 Apr 2007One and Only
S5E22 / 29 Apr 2007Two of Us
S5E23 / 06 May 2007The Beginning
S5E24 / 10 May 2007
Season 6
Lost Boy
S6E1 / 27 Sep 2007Clean Up
S6E2 / 04 Oct 2007Res Ipsa
S6E3 / 11 Oct 2007Baggage
S6E4 / 25 Oct 2007Run
S6E5 / 01 Nov 2007
Where & Why (II)
S6E6 / 08 Nov 2007Absalom
S6E7 / 15 Nov 2007Fight/Flight
S6E8 / 22 Nov 2007
One Wrong Move
S6E9 / 06 Dec 2007Claus and Effect
S6E10 / 13 Dec 2007
4G
S6E11 / 10 Jan 2008
Article 32
S6E12 / 17 Jan 2008Hard Reset
S6E13 / 03 Apr 2008A Bend in the Road
S6E14 / 10 Apr 2008Deja Vu
S6E15 / 24 Apr 2008A Dollar and a Dream
S6E16 / 01 May 2008Driven
S6E17 / 08 May 2008Satellites
S6E18 / 15 May 2008
Season 7
Closure
S7E1 / 23 Sep 2008
22 x 42
S7E2 / 30 Sep 2008Last Call
S7E3 / 14 Oct 2008True / False
S7E4 / 21 Oct 2008Rise and Fall
S7E5 / 28 Oct 2008Live to Regret
S7E6 / 11 Nov 2008Rewind
S7E7 / 18 Nov 2008Better Angels
S7E8 / 25 Nov 2008Push Comes to Shove
S7E9 / 02 Dec 2008Cloudy With a Chance Of Gettysburg
S7E10 / 16 Dec 2008Wanted
S7E11 / 06 Jan 2009Believe Me
S7E12 / 13 Jan 2009Once Lost
S7E13 / 27 Jan 2009Friends and Neighbors
S7E14 / 03 Feb 2009
Chameleon
S7E15 / 10 Feb 2009Skeletons
S7E16 / 17 Feb 2009Voir Dire
S7E17 / 17 Mar 2009Daylight
S7E18 / 31 Mar 2009Heartbeats
S7E19 / 07 Apr 2009
Hard Landing
S7E20 / 14 Apr 2009Labyrinths
S7E21 / 28 Apr 2009Devotion
S7E22 / 05 May 2009True
S7E23 / 12 May 2009Undertow
S7E24 / 19 May 2009
Anthony LaPaglia
Jack Malone
Poppy Montgomery
Samantha Spade
Marianne Jean-Baptiste
Vivian Johnson
Enrique Murciano
Danny Taylor
Roselyn Sánchez
Elena Delgado
