This dramatization of John Lennon’s teen years seems inspired as much by the remorseful wistfulness in Lennon’s songs as the biographical details of his life. It depicts the bittersweet birth of musical genius. According to the movie’s account, based on a memoir by his half-sister, Lennon was a product of a bewildering alchemy of repression, abandonment, sex and that revolutionary spark of the 1950s: rock and roll. The movie opens with Lennon (Aaron Johnson) living with his emotionally distant aunt (Kristin Scott Thomas), half aware that his mother, Julia (Anne-Marie Duff), has a house nearby with a new husband and two young daughters. One day, at Lennon’s insistence, the two reunite and form a strange relationship that winds its way to a tragic sort of reconciliation. Johnson manages to capture nearly all the qualities of the complicated Lennon: his cocksure playfulness, emotional vulnerability and capacity for casual cruelty (the latter of which may be a result of a combination of the former two traits). Duff’s Julia, meanwhile, is a disarming, disturbing creation. Possibly manic depressive, she’s a vibrant, sexual presence, even treating her initial encounters with her son as illicit dates. She also turns him on to rock and roll, whispering in his ear that the music is the equivalent of sex. It’s a queasy, uncomfortable relationship to watch, yet one that may explain not only Lennon’s lyrics, but also his personal recklessness. Come to think of it, this may even explain Yoko Ono.