A surgeon's morals are tested after he sets up an illicit clinic beneath London to save his wife's life.

The clinic's secrecy falls into jeopardy when Daniel puts Beth's ex-colleague Anna in an impossible position.

Daniel finds he's moving far away from the man he thought he was, as dealing with London's most dangerous people brings big problems.

Things grow complicated between Daniel and Anna as they battle to save someone they love. Lee takes a risk that endangers them all.

Daniel's descent reaches new depths as he enters the world of organ trading. As police and gangsters close in, Jamie makes an error.

Hall and Maloney get a break in their hunt for Jamie. Daniel faces the ultimate question - how far will he go for someone he loves?.

Daniel crosses a line from which he can never return. Lee's forced to make a big decision about the clinic. But will it be too late?.

As Mercy and Keith close in, Daniel, Lee and Anna discover just how far they'll go to save themselves.