Episodes 1.3 Burn Out: Part 1 (2001) & 1.4 Burn Out: Part 2 (2001) received 8.4 million viewers and a 38% audience share.
In the pilot episode (Pilot: Part 1 (2000) & Pilot: Part 2 (2000)) Boyd (Trevor Eve) had a wife and baby. However by S1 (Burn Out: Part 1 (2001) & Burn Out: Part 2 (2001)) he is very much single and instead has an older son, who is missing.
Mel (Claire Goose)'s name was originally just Mel in the Pilot episode (Pilot: Part 1 (2000) & Pilot: Part 2 (2000)). However by Series 1 (Burn Out: Part 1 (2001) & Burn Out: Part 2 (2001)) it had been extended to Amelia.