The phone rings in the emergency control room. It’s answered by an operator. After that, anything could happen. It happens day in day out, the call handler is just a voice but they’re talking to somebody at a critical moment. It’s a stressful job, the one at the centre of the new BBC One drama, The Control Room.

A tense thriller full of twists and turns, it’s about Gabe (Ian Caestecker), an emergency response handler whose life is turned upside down by a life and death 999 call. The voice on the other end of the phone is alarmingly familiar and the woman concerned (Joanna Vanderham) appears to know him as well. Under pressure to find out for sure who she is, Gabe makes decisions that threaten devastating consequences.

We sat down with the two actors to talk about their characters, both of whom have issues buried deep in their pasts, as well as the pressures that go with being a call handler and the multiple meanings of the series’ title. Some of the conversation took place with an emergency vehicle siren in the background. It was pure coincidence. We promise.

The Control Room launches on BBC One on Sunday, 17 July at 9 pm.