Tonight’s Casualty and Holby City crossover will see Sacha (played by Bob Barrett) involved in an unexpected car crash with his daughter Beka (Francesca Barrett).
A pregnancy test will fall out of Beka’s bag and shocked Sacha will take his eyes off the road.
He immediately asks his daughter if she is expecting and if the test belongs to her which leads to an argument.
Teasing details of the crash, Bob explained: “As they argue, Sacha takes his eye of the road… and that’s when another car hits us!
“The car rolls out of control and ends up upside down.”
Initially, it will appear that Sacha is okay as he manages to stumble out of the car while Beka has a broken leg.
However, later in the episode it will be revealed the doctor actually has a life-threatening injury.
“From the the impact of the crash, Sacha has suffered a blood clot and, in Tuesday’s Holby, the blood clot moves, Sacha’s collapses and it’s a race to see who can save him!” Bob added to What’s On TV.
However, when Sacha is rushed into the operating theatre, a cyber attack proves problematic as the medical equipment malfunctions.
Jac (Rosie Marcel) is busy operating on Sacha however, Connie Beauchamp (Amanda Mealing) is operating on Iain Dean (Michael Stevenson).
Viewers will see Jac and Connie arguing over needs to be saved as they are forced to make a decision.
Will they choose to save Sacha or will he perish?
It comes after actress Amanda spoke out on her future on Casualty hitting she could move over to Holby City.
“Do you know what? When I was there, I was walking around, thinking, ‘Do you know what? I’d like to come back, I think,” Amanda told Digital Spy.
“I really would. I do love it there, I really do. So we’ll see.
“I didn’t realised how much I loved it. I obviously have great affection for the show.
“But actually being back just reminded me that I have so many happy memories there.”
The synopsis for tonight’s crossover episode reads: “A cyber-attack rocks Holby hospital at the worst possible time.
“Meanwhile, Ruby learns to trust her instincts as Iain’s life hangs in the balance.”
Casualty/Holby City airs tonight on BBC One at 8.40pm.