The Mark of a Killer (2019)

Crime · Documentary

All serial killers commit murder to satisfy their grand fantasies, but the murderers featured in this true-crime docuseries take it one step further, committing heinous acts that allow them to extend their fantasies and relive the excitement of their crimes again and again.

IMDb rating: 7.4 (236 votes)
Episode average: 7.5 +0.1 vs IMDb
Seasons: 3
Streaming (US): Peacock
Language: EN
Type: TV series

Rating trend: this show's seasons do not settle into one shape. Rising Shows ranks whole shows by the shape of their rating trend rather than one average score, which is how you find a show that got better rather than a show that started well.

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Ratings refreshed Oct 3, 2026 · 3 seasons indexed

Seasons

Season 1 (2019)

7.65 avg 6 episodes 7.6 → 7.9 43 min avg

Season 1 episodes - IMDb ratings
#	Title	Rating	Votes
1	Posed to Kill	7.6	35
2	The Last Call Killer	7.6	33
3	An Eye for Murder	7.4	25
4	Pattern of Murder	7.5	22
5	Momentos of Murder	7.9	19
6	An Appetite for Murder	7.9	22

Season 2 (2020)

7.80 avg 10 episodes 7.3 → 8.3 43 min avg

Season 2 episodes - IMDb ratings
#	Title	Rating	Votes
1	Killer Caller	7.3	21
2	Deadly Summer	7.9	20
3	Deadly Design	7.4	20
4	The Other Zodiac	7.5	19
5	The Smell of Death	7.8	18
6	Hunted to Death	7.8	15
7	Collar and Leash Killer	7.7	20
8	Killer Athlete	8.0	18
9	Bound to Kill	8.3	18
10	Keys to a Killer	8.3	15

Season 3 (2021)

7.31 avg 14 episodes 7.4 → 8.5 46 min avg

Season 3 episodes - IMDb ratings
#	Title	Rating	Votes
1	The I-40 Killer	7.4	23
2	The I-95 Killer	7.1	17
3	The Charmer	7.2	20
4	The Englewood Killer	7.3	16
5	Classified to Kill	7.4	17
6	The Interstate Killer	7.1	17
7	The Grim Sleeper	7.3	15
8	The Tourniquet Killer	7.2	14
9	Deaths in the Desert	7.1	18
10	Summer of Fear	7.7	19
11	The Monster	7.3	12
12	The Bayou Strangler	7.1	14
13	The Skull Crusher	6.7	10
14	The D.C. Sniper	8.5	12