Players have a hand of cards, each representing stations on the London Underground. Each card shows the coloured underground lines served by that station. Some stations will be intersections of numerous lines, others will be on a single line. The first player lays a card face up and players in turn play cards that are on a line that matches that of the previous card. If they cannot lay a card, they draw a card. The winner is the first player to exhaust their hand. There are special cards that use phrases that will be well known to London Underground travellers and which affect game play. For example, 'Planned Engineering Works' allows a player to specify a line that is 'closed' and so cannot be played until that player's next turn. The short rules include a variant that allows multi-game scoring.

The cards replicate the iconic design of the London Underground map, and the game is licensed by Transport for London. It comes in a tin box that replicates the London Underground symbol (red circle crossed with a blue bar).