Local laws that catch crew out in London

Drug possession is charged by class and the maximum penalties are serious: up to seven years in prison, an unlimited fine or both for Class A, up to five years for Class B, and up to two years for Class C. Cannabis is Class B in the UK and is not decriminalised, whatever the position is where you are based.

Carry any medicine containing a controlled drug in your hand luggage when entering or leaving the UK, and be able to prove it is yours with a prescription or a letter from your doctor. If you are not a UK resident you need a letter of proof giving your name, your travel dates, a list of your medicine with quantities, doses and strengths, and the signature of the person who prescribed it. You can bring up to three months' supply, and anything above that will be taken away.

Knives are the law crew most often get wrong. It is illegal to carry most knives or any weapon in public without a good reason. The exception you can carry without one is a folding pocketknife with a cutting edge no longer than three inches that is not a lock knife, meaning it has no button, spring or catch you have to use to fold it. The maximum penalty for carrying a knife or weapon illegally is four years in prison, an unlimited fine or both.

On TfL buses, trams and trains, in bus and rail stations and on tram platforms you must not consume alcohol or be in possession of an open container of alcohol. TfL states you may be prosecuted if you disobey these requirements.