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Dateline S33E21 — Deadly Obsession

6.5

Dateline•Season 33•Episode 21

Deadly Obsession

6.5/10 · 33 votesApr 4, 202583 min

Ranked #31 of 34 in Season 33•−0.6 vs season avg

Mike Sisco and his fiancé Karen Harkness are found shot to death in their Topeka duplex in 2002. A years-long search for the killer and three criminal trials over two decades reveals strained dynamics within one victim’s family.

Previous episodeE20 · Poison Twist Next episodeE22 · The Last Mile

Seasons35

All 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35

Season 33 Episodes34

The Butterfly still

The Butterfly

Wrong Turns still

Wrong Turns

Down the Rabbit Hole still

Down the Rabbit Hole

The Night of the Nor'easter still

The Night of the Nor'easter

Deadly Omission still

Deadly Omission

After the Halloween Party still

After the Halloween Party

The Menendez Brothers: Chance at Freedom still

The Menendez Brothers: Chance at Freedom

Deadly Dance still

Deadly Dance

The Killer Among Them still

The Killer Among Them

The Man of Many Faces still

The Man of Many Faces

A Little Patch of Perfect still

A Little Patch of Perfect

Deadly Mirage still

Deadly Mirage

The Devil Wore White still

The Devil Wore White

Under the Bay Bridge still

Under the Bay Bridge

Return to the Lake still

Return to the Lake

A Walk Through the Woods still

A Walk Through the Woods

The Haunted House Confession still

The Haunted House Confession

Lori Vallow Daybell: The Jailhouse Interview still

Lori Vallow Daybell: The Jailhouse Interview

Deadly Entanglement still

Deadly Entanglement

Poison Twist still

Poison Twist

Deadly Obsession still

E21 6.5Now viewing

Deadly Obsession

The Last Mile still

The Last Mile

The Widow of Woodland Hills still

The Widow of Woodland Hills

The Pin at Apartment 210 still

The Pin at Apartment 210

The Devil’s in the Details still

The Devil’s in the Details

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Murder in Minot

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Secrets of the Sliding Door

The Terrible Night on King Road still

The Terrible Night on King Road

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Sean Combs on Trial

Center of the Storm still

Center of the Storm

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Sean Combs: The Insiders Speak

Secrets of Exam Room 9 still

Secrets of Exam Room 9

The Night of the Audition still

The Night of the Audition

The Betrayal of Sandra Birchmore still

The Betrayal of Sandra Birchmore

Cast1

Lester Holt

Lester Holt

Self - Host

Crew12

R

Ryo Ikegami

Editor

B

Billy Ray

Editor

J

Justin Smith

Producer

T

Thibaut Rigeot

Editor

I

Izhar Harpaz

Producer

J

Justin Cece

Editor

M

Michael Nardi

Producer

T

Tim Al-Harby

Editor

B

Bob Higgins

Producer

F

Frank Bido

Editor

L

Linda Diehl

Editor

R

Robert Buchanan

Producer

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Episode Summary

"Deadly Obsession" is episode 21 of Dateline season 33. It scored 6.5/10 from 33 votes, ranking #31 of 34 episodes this season (season average 7.1). It aired on April 4, 2025.

Next: E22 · The Last Mile Best of Season 33