My son started my 2010 Jetta TDI and left the key inside. The doors are all locked and its started with no way in. Can a locksmith unlock these cars?

call a tow company and see if they can get in it with there tools

its always good to have a spare set of keys handy incase this happens. About the only way i can tell you can open the car is by putting something plastic or rubber coated between the top of the door window frame and pry it back and slip a coat hanger in over your door release handle and pull. car alarm goes off but its the fast and easy way since slim jims dun work. there is also phone apps that allow you to remotely connect to your car especially for vw and audi cars. not sure if the 2010 are capable of it but the later models are. If the car has Bluetooth it certainly will work. most cars are connected to the internet these days like gm cars will send you a email if something is wrong after your last start up such as low tire pressure.