Tinseltown is an American style diner very popular with celebrities, they've recently expanded the franchise to the UK, and have branches all over including Hampstead.

Basically Food is over-priced and not very nice, infact my friend who ordered the italian pasta with chicken - his chicken was off and the pasta was cold.
However I got the chinese dish it was warm, and tasted alright however the chicken was also off!
The food and drinks are well over priced. The best thing out of the experience was the hot chocolate which was edible and actually tasty (but quite small + expensive)

The place is very popular, it is also halal, and "great for tourists", all over the walls there are pictures of celebrities sometimes the pitcures include the manager/boss of tinseltown standing with the celeb.

The one in central london opens 24 hours, so you can go any time.

For more info visit their website tinseltown.co.uk