Alison Herman TV Critic It’s hard to get a handle on “Mary & George,” the 17th-century historical drama that premieres on Starz this week after last month’s initial run in the U.K. The tale of how the title characters (Julianne Moore and Nicholas Galitzine) enmeshed themselves in the court of King James I (Tony Curran) through George’s seduction is intricate enough on its own, packing a dizzying array of alliances, betrayals, breakups and reconciliations into seven 50-minute episodes.