In a recent chat with What’s on TV Casualty star Crystal Yu reveals there’s a lot more to the single-minded medic than meets the eye.

Here Crystal speculates about the Chinese doctor’s mysterious family background and divulges what it was like working with Hollyoaks’ Gary Lucy in a special one-off episode…

This Saturday we see Lily turn detective in a special stand-alone episode. What can you reveal about the storyline and guest star Gary Lucy?
“This is Casualty on a very spooky night with murders happening in the hospital! Lily puts on her detective hat determined to figure out what’s going on. We have the wonderful Gary Lucy on this episode. He’s a lovely guy and a great actor and a bit of eye candy for the girls too!”

How was it working on the night shoots for this special spooky episode?
“It was a lot of fun to film, but there was also a lot of behind-the-scenes hysteria because we were all so tired from the night shoots! Amanda Henderson, who plays nurse Robyn, and I got really giggly during our scenes with Gary!”

What do you most enjoy about working with the guest stars Casualty attracts?
“To be able to work with guest artists who are so experienced in their field and know their craft so well is really inspiring for me. I feel really lucky to be doing this job.”

What is it about Lily that keeps you in Casualty and playing the character?
“I love playing her! She comes across as defensive and guarded so there’s got to be a history. Is she the way she is because of things that have happened in the past? It would be so interesting to see who Lily is behind closed doors. There’s more to discover. I’d love to explore who she is with her family and loved ones.”

When we first met Lily in 2013 she was single-minded in her ‘five year plan’. Is she still on track with that?
“Lily’s grown up a lot this past year or so working in the hospital. Initially she wanted to leave and go on to dermatology, where she’d probably make a lot of money, but now I think she’d miss the adrenaline and variety of her ED job and saving lives!”

Doctor Lily Chao is infamous for her cold, clinical demeanour. Isn’t it about time we saw her softer side?
“If you want to see Lily’s softer side you’ll have to wait a little bit longer. She has a heart and emotions. The episodes we’re currently filming see Lily crying her eyes out, but this is much further down the line.”

Watch BBC1 at 9.15pm on Saturday, November 15 when Lily lets her inquisitive nature run riot in a special one-off episode with Gary Lucy playing dodgy patient Valentine Kildare.

Read more about the spooky episode here.