If you're here after watching The Missing series 2 episode 5, welcome. If not, go away before you spoil the biggest twist of the series so far.

Still here? Right, it's time to talk about military press officer, main suspect and horrific power drill user, Adam Gettrick – played by Derek Riddell.

The character, seen in the previous episode when Gemma and Sam have to deal with press intrusion, has suddenly become a major character in The Missing's knotted mystery.

When German detective Jorn Lenhart arrived at his house at the end of episode five, asking questions about missing girl, he was surprised to discover a girl living in the house with him. A girl no one in the town even knew about. A girl who had drawn a very incriminating picture...

"That's me and Mummy. In the basement."

Gettrick is going to be an important part of the second half of The Missing, but what do we need to know about the actor who plays him, Derek Riddell?

Well, for a start, he's been admirably secretive about his key role in The Missing, barely mentioning the BBC1 series on Twitter over the past few weeks. Last month he tweeted that he "did a little bit" in the show. Not so "little" now...

The 49-year-old Scottish actor first made his name in Channel 4 drama The Book Group, before going on to appear in Clocking Off and No Angels. He also guest starred in US comedy drama Ugly Betty, as Ashley Jensen's alcoholic husband Stuart, as well as Doctor Who and Ripper Street here in the UK.

Recently Riddell also recently featured in series one of BBC1 drama Happy Valley, appearing as lead character Catherine Cawood's ex-husband Richard.

With a back catalogue like that, we should have known Riddell would have more to do than just pushing aside press photographers...

The Missing series 2 continues next Wednesday at 9pm on BBC1