The mission briefing

Torchwood, a BBC science fiction TV show, has kicked off an online alternate reality game (ARG) geared toward fans.

Users are given a mission briefing which states that people in the Welsh capital of Cardiff are being injected with alien DNA and must find a hidden signal to stop it, reports Reuters.

The multi-platform game includes a fake call-in show, a dating site and a faux biotech company. The firm is also working out how it can integrate the game with the TV show.

TV producer Sophie Fante said creating an ARG is all about planning. The more readily planners sort out the multi-platform elements, the more effective it will be.

See Related Stories for a list of other alternate reality games.