From bobbies on the beat to the glitz and glamour of life in the skies, ITV has a range of insightful documentaries in store for us this month. With Rookies, Virgin Atlantic: Up in the Air, Secret life of Twins, Vet School, and Joanna Lumley’s Trans-Siberian Adventure all showing on ITV. And if you miss an episode, you can catch-up on ITV Hub when it suits you. Secret Life of Twins (Wednesday 15 July at 21:00) Why are twins so fascinating? Genetics is a weird and wonderful thing – and at times unpredictable. Secret Life of Twins looks at the scientific research into the hidden, and sometimes surprising, differences between identical twins. Scientists have discovered that it’s not unusual for twins to react differently to illness. This episode looks at the health issues of Tim and James Brown from Liverpool, who both suffered kidney problems as toddlers and were treated in the same way. However, only James recovered fully. Joanna Lumley’s Trans-Siberian Adventure (Sunday 19 July at 21:00) It’s hard to think of a more delightful travel partner than Joanna Lumley. The likeable actress and model embarks on a 6,400 mile journey, taking her from Hong Kong all the way to Moscow. This week, Joanna spends time with some Mongolian nomads, visits a gold mine and a giant statue of Genghis Khan. She then moves on to the capital of Ulan Bator to track down the amazing Mongolian throat singers before catching the train to Russia – it’s all in day’s work for Ms Lumley. Vet School (Tuesday 21 July at 20:30) Get your cute fix for the week with Vet School. But be warned, poorly animals can make the hardiest tear up. This documentary looks at the pioneering work of the vets and students at the Edinburgh Royal School of Veterinary Studies as they treat a whole bunch of animals, from the everyday to the exotic. The test results are in this week. Find out why Bunny the horse is so sick. Meanwhile Tegan the cat is urgent need of help. And in rodent week in the small animal hospital, an unusual visitor turns up with the Scottish SPCA. Rookies (Monday 20 July at 21:00) Ever thought you could cut it in the police force? Watch Rookies and think again. Filmed over the course of a year, this series follows 24 people from all walks of life as they train to become police officers. This documentary focuses on the tough breaking in period. In this episode, 26-year-old Jack is reprimanded for not being proactive enough – he then stops and searches a completely innocent couple. Meanwhile, father-of-two Dan is struggling to make ends meet on a rookie’s salary. Virgin Atlantic: Up in the Air (Tuesday 21 July at 21:00) Virgin Atlantic prides itself on being a fun and glamourous way to fly – and now Richard Branson has let the cameras behind the scenes for the first time. This warm and humorous series tells the tale of a pivotal year for the airline. This time, Virgin Atlantic: Up in the Air sees the team finally get a chance to fly the new Dreamliner plane after seven years of waiting. However, the lighting has an unfortunate side-effect on the crews’ blouses.