'6 Underground'

Lily's swotting up on youth culture before meeting Sapphire that afternoon. Sapphire's not impressed with Lily's clumsy attempts to seem cool and calls her pathetic. She's sick of people lying to her but she finally realises that Lily made an effort – and that's something.

Cherry's trying to push the idea of Roller Camp onto Simon, but he gets angry and accuses her of only wanting to go to gay nights so she can meet someone like Scott. Cherry is hurt and Simon realises he's gone too far. Later he asks Cherry out for lunch to say sorry.

At the restaurant, Cherry reluctantly suggests they take a break from each other for a while, in order to protect their friendship and Simon agrees. When a diner begins to choke, Simon performs an emergency tracheotomy. One of the paramedics who arrives, Will Duncan (30), has a moment of connection with Simon…

Matthew's putting the word out that his Dad's business is back in Letherbridge, as he wants to build a future for Zara. Daniel sees Zara's twinging conscience but Zara won't engage with him. Later, Matthew opens some champagne – he's just got word that his Dad is flying in next week – and Zara is apprehensive.

Meanwhile, Sam Griffin (32) has a panic attack as he leaves a supermarket, thinking he's hearing the voice of his missing girlfriend Heather Taine (31) calling out for help. He goes to see Daniel and explains that Heather's been missing for six months. He filed a police report and now he's reduced to handing out photos of her around town.

Daniel recommends cognitive behavioural therapy but Sam refuses, he doesn't want to accept that she might never come back. Laura Birks (31) waits for Sam at home, a fellow member of his missing persons support group.

When she leaves to get them some lunch, Sam hears Heather's voice again and snaps, pulling up the rug and opening a tiny trapdoor to reveal Heather. Meanwhile Daniel, concerned about Sam, rings Rob to see if anything else can be done about Heather, but Rob says no report has been filed. Sam opens a larger trapdoor to talk to Heather, telling her that she needs to stop fighting him. She resists, so Sam gives her some more drugs.

Through flashback, we see that when Heather wanted to split up with Sam, that's when he took action.

As Laura returns, Sam closes the trapdoor, but when Laura makes a move on him he gets distressed, knowing his girlfriend is so close. To apologise, Laura calls Heather's mum to tell her she's going to help Sam find Heather.

As she's crossed a line, Sam slides open a drawer to get a syringe for an unsuspecting Laura, who sees Daniel arrive and lets him in. Sam denies he was lying earlier and when Sam lunges at him, Daniel is able to restrain Sam and Laura realises that Heather is under the floorboards.

As Sam is lead away by the police, he's sure that they've ruined Heather's chance of being happy.