BSkyB's first free-to-view entertainment channel on the Freeview digital TV service has made its debut.
The third series of US drama 24 will be shown on Sky Three
Sky Three will feature programmes already seen on Sky One as well as original travel and lifestyle shows. It replaces Sky Travel on Freeview.
Early schedule highlights will include the first free-to-view broadcast of the third series of US drama 24.
ITV's new digital channel aimed at men, ITV4, will launch on Tuesday, featuring a mix of drama, film, comedy and sport.
Its line-up includes the new series of Kojak starring Pulp Fiction's Ving Rhames and crime drama Wanted. It will also screen Champions League football.
Sky Three replaced the Sky Travel channel on Freeview from 1700 GMT on Monday. Sky Travel will continue to broadcast as a separate channel on Sky Digital and cable.
Sky One shows to transfer to Sky Three, which is also available via Sky Digital, will include US crime drama Cold Case and hypnotist Paul McKenna's series I Can Change Your Life.
The existing digital and cable Sky Mix channel, which also shows old Sky One programmes, will be renamed Sky Two.
As well as reaching the 5.2 million households which have Freeview, Sky Three will be available to the 7.8 million homes which subscribe to Sky.