Teenage student Richard Samuels (Zac Efron) lucks his way into a minor role in the legendary 1937 Mercury Theatre production of Julius Caesar, directed by a youthful Orson Welles (Christian McKay). Over the course of a magical week, Richard makes his Broadway debut, finds romance with an ambitious older woman (Claire Danes), and experiences the dark side of genius after daring to cross the imperious, brilliant Welles. Richard has to grow up fast.

Period drama puts on quite a show.

Richard Linklater’s best movies are concerned with the ramifications of impetuousness: a young man and a young woman meet on a train and decide to spend a night together exploring Vienna (Before Sunrise), a broke slob impersonates his roommate, a substitute teacher, to make some money (School of Rock). The Austin-based filmmaker allows impulsive decisions to unfold, which naturally makes the young (and the merely madly irresponsible) his natural constituency. Adulthood, or at least responsibility, is always looming.

His new feature, Me and Orson Welles, continues this thematic tradition even as the storyline and setting once more change. This time it’s 1937, a period for which he has the appropriate leading man-child, in the form of High School Musical tween heartthrob Zac Efron. The matinee idol throwback plays Richard Samuels, a high school senior who believes his education is best completed on the streets of New York. Impishly confident but nonetheless an innocent, Richard talks his way into the ranks of a theatre company.

In the screen adaptation by Holly Gent Palmo and Vincent Palmo Jr. of Robert Kaplow’s historical novel, Richard is a fictional character but his employer most certainly isn’t. Based on 41st Street at the time, The Mercury Theatre Company was marshaled by Orson Welles (Christian McKay) and John Houseman (Eddie Marsan), and it was renowned for their innovative Shakespearian productions. The teenager is cast as Lucius, a minor part in what is now considered a theatrical landmark, a starkly blazing, fascist Italy-themed take on Julius Caesar.

The film is at once the study of how collective greatness arrives with mundane preparation (the actors gossip, flirt and worry about their scenes being cut) and how individual greatness arrives in an ambulance, full of ideas and accusations too time-consuming to pursue. As Welles, classically trained British actor Christian McKay delivers a performance that captures the immense appetites of his subject, whether it is for food, adulation, the credits or the opposite sex. It’s florid and compelling, a portrait of Welles the theatrical genius prior to taking up RKO’s offer to come to Hollywood.

McKay’s performance is so complete that you forget that Welles was just 22-years-old at the time (McKay is in his mid-30s). Nonetheless you get a sense of his oversized ego, his creative curiosity and his radical approach to written texts (with Richard in tow Welles dashes through a day job broadcasting a radio play, improvising dialogue from a notable book he’s reading, Booth Tarkington’s The Magnificent Ambersons). Welles is seductive and so is the world he has created in his orbit, and one of the subtle pleasures of Linklater’s film is how it reminds us that creative endeavours are founded on romantic hopes that are often dashed.

Linklater’s works often run loosely – his feel for plot is rarely concise. But with this milieu, where Joseph Cotton (James Tupper) is trying to pick up everything in a skirt and Norman Lloyd (Leo Bill) is fearful his Cinna the Poet scene will be sacrificed by the capricious Welles, the director can make salient points and have fun. Once he gets a burst of pop culture identification out of the way – when Richard meets fellow hopeful Gretta (Zoe Kazan) and they throw the names of their favourite artists back and forth to establish the cultural era – Linklater shows us both the power of Welles’ striking production and his casual cruelty.

It helps that Claire Danes is present as Sonja Jones. Ever since Romeo + Juliet great things have been expected of her, and she’s delivered them in the small films that have delineated the failed blockbusters. As with Igby Goes Down, Danes plays a young woman all too well aware of her beauty and what it is worth. Sonja treats her dalliance with Richard as just that, and there’s a screwball promptness to her dialogue that gives the picture welcome momentum.

Linklater has the best of both worlds with Me and Orson Welles: investigating the period setting and capturing a sense of one of the 20th century’s true artistic geniuses, while working through a coming of age tale that’s thematically related to his prior works. It’s not as far from the small town '70s Texas of Dazed and Confused to backstage at the Mercury Theatre on opening night in 1937 as you might think.