Colin Farrell as David

Margot Robbie as Sarah

Jennifer Grant as David's Mother

Hamish Linklater as David's Father

Phoebe Waller-Bridge as Female Cashier

Kevin Kline as The Mechanic

Jodie Turner-Smith as GPS (voice)

Lily Rabe as Sarah's Mother

Billy Magnussen as The Man

Chloe East as Cheryl

Lucy Thomas as Amanda

Sarah Gadon as The Woman

Brandon Perea as Mike

Calahan Skogman as Sarah's Groomsman

Jacqueline Novak as Stacy Dunn

Michelle Mao as Smitty

Jason Kravits as Mr. Nelson

Shelby Simmons as Stage Manager

Simon Khan as Tate Chandler

Yuvi Hecht as Young David

Mike Meldman as Father of the Bride

Pablo Soriano as Vincent

Galen Hooks as Choreographer

Brooke Maroon as Amy Moore

Julian Zane as Eddie Bora

Liz Jenkins as Another Mother

Gabriella Surodjawan as Miss Jones

Joyce Guy as Doctor Vernon

Karah Donovan as Nurse

Mia-Carina Mollicone as Hotel Receptionist

Aaron Quini as Student Performer

Carissa Rae Martin as Student Performer

Jarvis Langster as Student Performer

John Arthur Mays as Student Performer

Kayla LaVine as Student Performer

Mariah Spears as Student Performer

Phi VoBa as Student Performer