Sienna frantically calls the police about an intruder, telling them to send someone quickly and also to contact Greta Jackson from the Witness Protection Unit.

SIENNA:(fearfully) He's inside...

Meanwhile, Brennan is tackling the intruder.

BRENNAN: Car's on its way. You'd better get out of here while you can.
INTRUDER: That's OK, traitor. This won't take long.

Brennan launches himself at the guy and a fist fight ensues.

Sienna is still on the phone to the police as Brennan and the intruder continue to fight. Eventually, Brennan lays the guy out but he too is left lying on the floor, injured.

As the sirens blare, the intruder wakes up and Sienna screams. In slow motion, the intruder reaches for his weapon, but the police have arrived. A shot rings out. Fade to black.

Cut to a well- lit hospital room. Brennan comes round slowly and Sienna is there.

BRENNAN: Sienna. What are you doing here?
SIENNA: I didn't want you to wake up alone.
BRENNAN: What about Holland? Did they catch him?
SIENNA: He was shot, he didn't make it to the hospital.
BRENNAN: He's dead?
SIENNA: Yep.
BRENNAN: So sorry you got sucked into all this. It's the last thing I wanted...
SIENNA: It's not your fault.
BRENNAN: A lot of cops would say otherwise. I should have just shut my mouth.

She passes Brennan a drink.

BRENNAN: How long have I been out?
SIENNA: Three days...you've lost a lot of blood. They didn't think you'd make it.
BRENNAN: And you've waited around this whole time?
SIENNA: It's not like I had anything better to do.
BRENNAN: And you seriously wanted to stick around after all this?
SIENNA: What can I say? Guess I've got a soft spot for men with mysterious pasts.

He takes her hand.

Later, Brennan is recovered and back at his flat. The witness protection officer comes to see her, and Brennan tells her that she can talk in front of Sienna.

GRETA: In that case...
BRENNAN: What's this?
GRETA: All of the paperwork to officially end your time here in witness protection.

Brennan looks surprised.

BRENNAN: You're cutting me loose?

GRETA: Well, with Holland dead and the taskforce, there's no- one else who's going to come after you. Your life is officially yours again.

Brennan looks emotional.

SIENNA: Are you OK?
BRENNAN: ...Yeah. I've just spent a long time living with this.
GRETA: Tell me about it.
BRENNAN: What? So that's it? You're just dumping me and running?
SIENNA: Does that mean you can go back to being Mark again?
GRETA: He can do whatever he likes...just try to stay out of trouble, OK?
BRENNAN: I will. And Greta...thanks.

She smiles and nods, and then leaves Brennan's apartment.

A bit of a silence descends.

BRENNAN: Are you OK?
SIENNA: Yeah...this is all great. You get to have your life back again.
BRENNAN: It's going to take a while to sink in, though.
SIENNA: You can do whatever you want to do.
BRENNAN: You know what I want to do right now, more than anything?

He pulls her on to the sofa with him and kisses her.

A FEW MONTHS LATER

Sienna finds Brennan looking at a photograph on himself with Kate. She babbles about groceries but looks upset.

SIENNA: Will you please talk to me? I can't stand seeing you like this.
BRENNAN: There's nothing to talk about.
SIENNA: Yes, there is. We've been living together for months. We go climbing every weekend together, but...
BRENNAN: But what?
SIENNA: There's this part of you that you keep locked inside.
BRENNAN: Sorry.
SIENNA: It's about her, isn't it. The girlfriend that you never talk about. Did you really love her that much?
BRENNAN: Yes. (Off her look) You wanted the truth.
SIENNA: Do you love me?
BRENNAN: You know that I do.
SIENNA: But you still want to be with her.
BRENNAN: It's not as black and white as that.
SIENNA: Seems pretty black and white to me.
BRENNAN: I can't get her out of my head, OK? The way that things ended...I mean, she thinks that I'm dead! And it kills me that she thinks that. Can you understand that?
SIENNA: ...I guess. What do you want to do?
BRENNAN: I think I need to and see her and speak to her.
SIENNA: I don't even know where you lived!
BRENNAN: Down south in Melbourne...Erinsborough.

Sienna looks upset.

SIENNA: How long will you be gone for?
BRENNAN: A few days. Maybe a week. Si...I don't want to hurt you.

He hugs her from behind.

SIENNA: I know...but you can't keep going on like this. You have to make a decision once and for all.

She turns to face him.

SIENNA: Just...just, go. I'll be fine.

He kisses her and then heads off, leaving Sienna to cry quietly to herself.

Brenna is walking down a road as darkness falls.

BRENNAN (voiceover): "There are so many things I want to say to you, Kate. I don't know where to begin. I never stopped thinking about you. God knows I tried. Something in me just wouldn't let go. No matter what I do, I can't stop loving you."

BRENNAN RETURNS TO NEIGHBOURS

5th FEBRUARY 2014 on 11
19th FEBRUARY 2014 on Channel 5