Hollyoaks: Trevor and Grace's story. (When Trevor's seen on the phone; he's talking to Mercedes - I accidentally cut the bit off where he says her name, sorry.)
Other characters you might not recognise if you're a new viewer:
Tegan Lomax (along with her family: Sam, Danny, and Leela Lomax) - daughter of Sam, the police officer who questions Trevor in this episode. She's in hospital as Grace accidentally hit her, assuming she was Mercedes. Tegan's storylines are also going to be closely linked in with the Blacks as you'll find out by the end of this episode.
Superintendent Marlow - Sam's superior; he obviously works in the force but is corrupt.