Prior to his heartbreaking performance on HBO's The Wire, Michael B. Jordan played a childhood bully in season one.
Hamilton creator Lin-Manuel Miranda got his "Shot" with a cameo as a hotel bellman.
Emmy nominee Paul Dano portrayed A.J.'s friend Patrick Whalen across seasons four and five, before going on to play The Riddler in the upcoming The Batman movie.
Before she ruled the House of Gucci, Oscar winner Lady Gaga a.k.a. Stefani Germanotta wrecked havoc at a high school at age 15, alongside A.J. Soprano (Robert Iler) in an uncredited season three role.
Before The Morning Show and BoJack Horseman, comic actor Will Arnett played a FBI agent who was married to an undercover operative trying to infiltrate the Soprano crime family.
It's a mini Arrested Development reunion! Tony Hale starred as a chemotherapy nurse treating Uncle Junior (Dominic Chianese).
The Good Wife used to be a not-so-good mistress. Julianna Margulies played recurring season six character Julianna Skiff, who caught Tony's eye before having an affair with Christopher Moltisanti (Michael Imperioli) and becoming addicted to heroin.
Actor-director-producer Jon Favreau played himself, as Christopher tries to get him to direct his screenplay.
The late talent Michael K. Williams played Ray Ray, a mob affiliate who lets Jackie Jr. (Jason Cerbone) hide out at his apartment. The Emmy-nominated star later went on to have a breakout role in fellow HBO series, The Wire.
Cristin Milioti wasn't really Made For Love playing the daughter of New York's ill-fated crime boss Johnny Sack (Vincent Curatola).
Ari Graynor stole scenes as the neurotic college student—and roommate—Meadow (Jamie Lynn Sigler) struggled to relate to.
Former Daily Show correspondent Aasif Mandvi was the doctor who treated Phil Leotardo (Frank Vincent) for stress-related heart pain.
Tim Daly simultaneously starred on Grey's Anatomy spin-off Private Practice while playing Christopher's screenwriter pal, J.T. Dolan.
Grey's Anatomy star Chandra Wilson stole a season five episode as a woman who takes on Janice (Aida Turturro) during an anger management meeting.
It's a Shondaland party! Scandal star Guillermo Diaz started out as a pesticide salesman in season one.
Diaz's Scandal co-star Katie Lowes dated A.J. during season five.
Before appearing on House of Cards, actor Michael Kelly played an FBI agent investigating Tony.
Comedian Mike Epps played a car thief who took A.J.'s science teacher's ride in a hilarious Sopranos side story.
We've heard of Stranger Things than this, but it's hard not to do a double take watching Cara Buono play Christopher's wife Kelli Lombardo in the sixth season, knowing that she truly belongs on Mad Men.
What's Cleaver without Daniel Baldwin's spot-on performance? The Baldwin brother acted as himself in the lead role of Christopher's movie.
Like Tony, we also dream of Annette Bening...although not always as our in-law! The Oscar winner appeared in a fantasy sequence as herself-slash-the mother of Meadow's fiancé.
It doesn't get more Jersey than the the ultimate Jersey Boy. Famed crooner Frankie Valli played mobster Rusty Millio during the fifth and sixth seasons, with his songs being used throughout the show.
Screen legend Lauren Bacall portrayed a sassy version of herself—who later gets mugged by Christopher—in a Los Angeles-based episode.
In the same episode, filmed at the Viceroy Hotel in Santa Monica, Wilmer Valderrama has a mini cameo as himself, posing for paparazzi.