Updated: 31 Jan 2021, 13:36 JENNA Coleman fans will see the actress take on a very different role as she stars in BBC One's new crime show The Serpent, which is on tonight (January 31). The former Emmerdale star plays the partner and accomplice of French serial killer Charles Sobhraj in the new drama. 3 What time is it on BBC One tonight? Episode six is on BBC1 at 9pm tonight. In it, with a police investigation pending, a nervous waiting game ensues for Charles Sobhraj to return to Kanit House with Marie-Andree and Ajay, however, he might be one step ahead of the operation.