Secret Service 9pm, ITV1 Gemma Arterton stars as MI6 officer Kate Henderson in a tense, ambitious espionage thriller. Henderson heads the Russia desk and is disturbed by evidence suggesting the presence of a mole in the government. It soon looks as if she might not know the half of it. Cue twists galore as Henderson’s job and family life become dangerously intertwined. Phil Harrison Great Japanese Railway Journeys 6.30pm, BBC Two A Shinkansen bullet train hurtles Michael Portillo to the “mega metropolis” of Tokyo. We meet Minoru Mukaiya, composer of 300 catchy jingles for train station platforms, and ride the elevator to the top of the 630 metre-high, earthquake-proof Tokyo Skytree: “This technology just leaves me breathless.” Ali Catterall Mint 9pm, BBC One Charlotte Regan’s Romeo and Juliet remix set amid warring crime families in Scotland is earthy, formally inventive and – crucially – deeply heartfelt.…