Daily TV & movie popularityDaily TV & movie popularity
Top TVTop Movies
Top Lists
Search...
I Know This Much Is True

I Know This Much Is True Cast

80 cast members · 27 with active Attention Score
Popularity Stats
Compare
Top Cast
Episode Ratings
Similar Shows

Most Popular I Know This Much Is True Cast Members

Mark Ruffalo is currently the most popular I Know This Much Is True cast member online with a Attention Score of 11.8. 3 of 80 cast members rank in the top 1,000 actors online today. Updated August 6, 2026.

1
Mark Ruffalo
Dominick Birdsey / Thomas Birdsey · 6 eps
11.8
#118 overall
2
Juliette Lewis
Nedra Frank · 2 eps
5.1
#681 overall
3
Kathryn Hahn
Dessa Constantine · 6 eps
5.0
#713 overall
4
Rosie O'Donnell
Lisa Sheffer · 6 eps
3.2
#1,546 overall
5
Imogen Poots
Joy Hanks · 3 eps
3.2
#1,559 overall
6
Bruce Greenwood
Dr. Hume · 2 eps
1.5
#4,034 overall
7
Melissa Leo
Concettina Ipolita Tempesta 'Ma' Birdsey · 6 eps
1.2
#5,119 overall
8
Aisling Franciosi
Young Dessa Constantine · 2 eps
1.1
#5,598 overall
9
Tatanka Means
Nabby Drinkwater · 2 eps
1.0
#6,149 overall
10
Archie Panjabi
Dr. Patel · 6 eps
0.9
#6,863 overall
11
Rob Huebel
Leo · 6 eps
0.8
#7,846 overall
12
Harris Yulin
Father Lavie · 1 eps
0.6
#9,758 overall
13
Guillermo Díaz
Sergeant Mercado · 1 eps
0.5
#10,906 overall
14
Destry Allyn Spielberg
Dr. Hume's Daughter · 1 eps
0.5
#11,892 overall
15
Laura Silverman
Kristin · 1 eps
0.4
#12,680 overall
16
Felix Solis
Nurse · 1 eps
0.3
#15,834 overall
17
Michael Greyeyes
Ralph Drinkwater · 6 eps
0.2
#18,056 overall
18
Brian Goodman
Al · 1 eps
0.2
#20,814 overall
19
Joe Grifasi
Steve Falice · 1 eps
0.1
#27,358 overall
20
Philip Ettinger
Early Adulthood Dominick Birdsey / Thomas Birdsey · 2 eps
0.1
#30,817 overall
21
Gina Costigan
Mrs. O'Meara · 1 eps
0.1
#33,701 overall
22
Brandon J. Dirden
Kyle's Dad · 1 eps
0.1
#33,742 overall
23
Marylouise Burke
Librarian · 1 eps
0.1
#36,627 overall
24
Michael Genet
Thomas' Surgeon · 1 eps
0.0
#47,127 overall
25
Marcello Fonte
Domenico Onofrio Tempesta · 2 eps
0.0
#47,633 overall
26
Christopher J. Hanke
Thad · 1 eps
0.0
#56,403 overall
27
Laura Esterman
Ruth Hood · 3 eps
0.0
#57,934 overall
28
John Procaccino
Ray Birdsey · 6 eps
·
29
Gabe Fazio
Shawn Tudesco / Dominick and Thomas Acting Double · 6 eps
·
30
Sue Jean Kim
Dr. Yup · 1 eps
·
31
Michael Simon Hall
Stuart Feinstein · 1 eps
·
32
Steven Cox
Boyfriend of Dr. Hume's Daughter · 1 eps
·
33
MorningStar Angeline
Nabby Drinkwater's Wife · 1 eps
·
34
Al Linea
Abruzzi · 1 eps
·
35
Richard Fitch
Mill Foreman · 1 eps
·
36
Amy Lynn Stewart
Merciful Mother · 1 eps
·
37
Tim Ruddy
Robocop · 1 eps
·
38
Sandra Berrios
Social Worker at Hatch · 1 eps
·
39
Christine Parks
Humanities Department Chair · 1 eps
·
40
Morgan Sullivan
Office Buddy · 1 eps
·
41
Jake Robards
Landlubbers (voice) · 1 eps
·
42
María Gonzalez
Ma's Oncology Nurse · 1 eps
·
43
A.C. Peterson
Gene Diogenes · 1 eps
·
44
James Quattrochi
Bus Driver · 1 eps
·
45
Rachel B. Joyce
Jeanette · 1 eps
·
46
Paul Coleman
Support Group Counselor · 1 eps
·
47
Katt Masterson
Doreen · 1 eps
·
48
Jason Furlani
Larry Penn · 1 eps
·
49
Annie Fitzgerald
Miss Hanker · 2 eps
·
50
Kate Grimes
English Professor · 1 eps
·
51
Joseph Ragno
Henrey Rood · 1 eps
·
52
Acahkos Johnson
Penny Ann Drinkwater · 2 eps
·
53
Jaiden Klein
Marie Sexton · 2 eps
·
54
Charlie Reina
Channy · 2 eps
·
55
Violet Adams
Bunny Borsa · 2 eps
·
56
Oliver Patnode
Otero · 2 eps
·
57
Chelsea Sheets
Brunette · 1 eps
·
58
Matt Helm
Young Leo · 2 eps
·
59
Derek Goh
17-19 Year Old Dominick & Thomas Acting Double · 2 eps
·
60
Raymond Neil Hernandez
Omar · 1 eps
·
61
Simone Coppo
Vincenzo Tempesta · 1 eps
·
62
Sean Cullen
Dr. Yates · 1 eps
·
63
Federico Dordei
Nunzio Tucci · 1 eps
·
64
Agatha Nowicki
Angie Constantine · 2 eps
·
65
Rocco Masihi
Young Thomas Birdsey · 4 eps
·
66
Irene Muscara
Prosperina Tucci · 2 eps
·
67
Adrienne R. Williams
Mrs. Birdsall · 2 eps
·
68
Shannon Plumb
Charlotte · 1 eps
·
69
Donnie Masihi
Young Dominick Birdsey · 4 eps
·
70
Zaria Degenhardt
11 Year Old Concettina · 1 eps
·
71
Mark A. Gamma
Mourner Mark · 1 eps
·
72
Wayne J. Miller
Mourner Wayne · 1 eps
·
73
Thomas Gionet-Lavigne
Ray's Orderly · 1 eps
·
74
Alexander Hacker
Templeton · 1 eps
·
75
Robert Mladinich
Paddy Wagon Officer · 1 eps
·
76
Roberta Riganò
Ignazia Tempesta · 1 eps
·
77
Tim Ruddy
Robocop · 1 eps
·
78
Ethan Crystal
Thin Sailor · 1 eps
·
79
James Pravasilis
Third Guard · 1 eps
·
80
Michael Armand DeMatteo
Fatso · 1 eps
·
televisionstats.com
Cast Popularity FAQ
Who is the most popular I Know This Much Is True cast member right now?
Mark Ruffalo is currently the most popular I Know This Much Is True cast member online, with a Attention Score of 11.8 and an overall actor rank of #118 as of August 6, 2026.
How many cast members does I Know This Much Is True have?
I Know This Much Is True has 80 credited cast members. 27 of them have an active Attention Score on Television Stats today.
Which I Know This Much Is True cast member has the highest career peak?
Kathryn Hahn has the highest Peak Attention Score among the I Know This Much Is True cast, reaching 36.1 at their career high.
How many I Know This Much Is True cast members are in the top 1,000 actors today?
3 of the 80 I Know This Much Is True cast members currently rank within the top 1,000 most popular actors online on Television Stats.
televisionstats.com
I Know This Much Is True Stats›
Top HBO Shows›
Top Drama Shows›