Gridlock is an Irish

Ireland

Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...

 television game show

Game show

A game show is a type of radio or television program in which members of the public, television personalities or celebrities, sometimes as part of a team, play a game which involves answering questions or solving puzzles usually for money and/or prizes...

, hosted by Derek Mooney

Derek Mooney

Derek James Mooney is an Irish radio and television presenter, as well as a radio producer. He currently presents a weekday afternoon programme called Mooney on RTÉ Radio 1....

, that premiered on RTÉ

Raidió Teilifís Éireann

Raidió Teilifís Éireann is a semi-state company and the public service broadcaster of Ireland. It both produces programmes and broadcasts them on television, radio and the Internet. The radio service began on January 1, 1926, while regular television broadcasts began on December 31, 1961, making...

 on September 14, 1998. Gridlock replaced the long running series Blackboard Jungle which was hosted by Ray D'Arcy

Ray D'Arcy

Raymond 'Ray' D'Arcy is an Irish television and radio presenter. He currently presents a weekday morning radio programme, The Ray D'Arcy Show, on Today FM...

.

The show lasted only one season. There were two teams of two people, each team representing a secondary school. One player on each team would answer general knowledge questions, while the other would try to achieve "gridlock" on a puzzle diagram.

Due to the complex nature of the puzzle, viewers, the studio audience, and sometimes even contestants, struggled to follow the show. As a result of this, ratings dwindled and Gridlock was canceled after just one series.