When you’re starting out as an actor, one of the most confusing parts of casting calls is the sheer variety of labels used. In screen work, you may be thinking: What is the difference between a supporting actor and a guest star? In theatre, is there actually anything that separates an understudy from a swing?
It can be a minefield, but understanding the roles is essential because it means you know what kind of job you’re going for. Each role comes with different responsibilities, levels of visibility, and pay. Here’s a breakdown of the main acting roles in film, TV, and theatre, and what they mean for your career.
Screen acting has its own set of hierarchies and job titles. They can vary slightly depending on whether you’re working in the UK, US, or internationally, but here are the most common ones you’ll encounter.
Lead actor
In film, the lead actor is the central character or the person the story revolves around. In TV, a lead actor will usually appear in every episode. Think Emma Stone as Mia Dolan in the film La La Land or Paul Mescal and Daisy Edgar-Jones as the joint leads on the TV show Normal People. The roles are highly competitive, and although they tend to go to established actors, newer actors sometimes break into them. “As the central figure, the lead actor often carries the weight of the narrative, commanding the most dialogue and occupying the majority of screen time,” Kyle Deguzman writes for StudioBinder.
Supporting actor
A supporting actor often plays the best friend, rival, or mentor figure. The roles often have substantial screen time and can be career-making. In 2025, Jessica Gunning earned a BAFTA for her supporting role in Richard Gadd’s drama Baby Reindeer. Supporting actors are essential to the narrative. “Supporting actors aren’t just those familiar faces who can steal a film,” David Thomson writes in the Guardian. “They show a way for movies to portray real life.”
Recurring role
Recurring roles often appear on TV series and may be defined as characters who appear in multiple episodes but not every one. They help build out the world of the show and may take the form of teachers, bosses, or neighbours. Getting a recurring role can provide consistent work and visibility. Olivia Colman’s role as Mark’s coworker Sophie on Peep Show is a great example.
Guest star
A guest star usually features in one episode, with a storyline centred on them. Guest-star roles are common stepping stones for actors breaking into the industry. Andrew Garfield starred in two episodes of Doctor Who in 2007, long before his success in The Amazing Spider-Man. But celebrities may also take guest-star roles. On Glee, they became a recurring feature: celebrities including Britney Spears, Gwyneth Paltrow, and Sarah Jessica Parker all starred in episodes across the series.
Extra
Extras don’t have lines, but they help populate a scene. They may fill a restaurant, crowd, or street, and although the job may not be performance-heavy, it’s a useful way to learn how a film set operates and start building credits. “Extras aren’t supposed to say anything during a take, for, as the saying goes, you aren’t being paid to talk,” an anonymous extra writes in the Guardian. Even so, it’s not uncommon for extras to be used as stand-in actors, or even end up working their way into jobs behind the camera.
Theatre has its own language when it comes to casting. Here are some of the main roles you may find for the stage.
Lead actor
Like in film, stage shows have a lead actor – or principal, as they’re commonly known in the US. Famous roles include Elphaba in Wicked or Hamlet in Hamlet. Leads carry much of the narrative weight and are usually seen on the posters advertising the show. It can be difficult for actors starting out to be cast as leads fresh out of drama school, but it does happen. Sam Tutty, for example, was immediately cast as Evan Hansen in Dear Evan Hansen after graduating from Italia Conti.
Supporting actor
A supporting role may have less stage time than a principal, but they’re still important. In a musical, they may even have their own songs or feature in several scenes. Drama school graduates may be looking to bag one of these roles. Amara Okereke, for example, won the role of Cosette in Les Misérables shortly after graduating from ArtsEd in 2018.
Understudy
An understudy learns the lines, blocking, and songs for a principal role and is ready to step in at short notice if the main actor cannot perform. “An understudy is typically an actor who’s in the main company of a production,” Sophie Thomas writes for London Theatre. “Usually, understudies are part of the ensemble in a show, but they can also be called upon to perform on select days if a main cast member is sick.” Producer Nica Burns even called them “the backbone of the industry.” It can be a vital training ground, with actors learning how to step up at short notice. Many famous actors, including Paapa Essiedu, who stepped in to play Edmund in Sam Mendes’ King Lear at the National Theatre in 2014, began their careers as understudies.
Swing
A swing is a type of understudy who covers multiple ensemble roles known as “tracks.” They may go on for several different roles during a production’s run. It’s often described as one of the most difficult jobs in theatre, because swings need encyclopaedic knowledge of the show. “Swings are an integral part of a company, and sometimes have the hardest part to play,” Thomas says. “They can step into productions in a variety of instances.” On the first UK tour of Six, for example, Grace Mouat, who had just graduated from the musical theatre course at Guildford School of Acting, was cast as a swing for all the queens.
Ensemble or chorus
The ensemble is the backbone of most musicals and many plays. The actors sing, dance, and act in group numbers while sometimes covering smaller featured parts. It’s highly physical work and a great way to learn the ropes in theatre. “Since the earliest days of theater as an art form, ensemble members have helped to immerse the audience in the world of the show, creating the platform for the story to unfold,” according to the Boston Conservatory of Berklee.
Whether you’re auditioning for a series regular on a TV show or to be part of the ensemble in a West End musical, each role is distinct and essential. Early in your career, you may not land a lead role, but that doesn’t mean you won’t get there eventually. Playing various roles will build your repertoire – and you never know where one role may lead.