in my editing of my script (didn't finish it in time/oh well)
my character needs to get from Harvard Law to London and this may sound stupid (it does) but you would need to take a plane then a train to get there?
the plane for overseas and the train to get into the city?

thank you

There are two major International Airports serving London: Heathrow and Gatwick.
Transportation to and from London can be accomplished by subway, bus, or taxi.
From Harvard Yard in Cambridge I believe bus and taxi would be the preferred methods of transportation to Logan Airport in Boston. Subway is possible but would involve several transfers making it terribly inconvenient for someone with luggage.
I hope this helps.

"It's never too late to become what you might have been."
- George Eliot

From Heathrow (west) or Gatwick (south) the simplest transfer is the train. The Heathrow Express gets you into Paddington in West London in 15 minutes and the Gatwick Express into Victoria (South London) in 30 minutes. Both run a service every 15 minutes.

You can get the tube (underground railway) from LHR, which is better if you are travelling on into Central London, but it doesn't reach out to LGW.

Taxis are relatively expensive and get stuck in traffic. Buses only slightly better unless you are travelling to places other than London.

If you are anything more than unimportant, your company would send a driver to meet you in the airport concourse - either one of their own, or for a smaller company, a minicab (private hire).

HTH