06/02/2017 12:08 GMT | Updated 06/02/2017 12:08 GMT

'Apple Tree Yard': 6 Questions We Have Ahead Of Tonight's Final Episode 4

Who's going down?

Well, it’s all officially hit the fan now in ‘Apple Tree Yard’, with Yvonne (Emily Watson) being arrested for the murder of George Selway, and the tatters of her life becoming clear - and that was before she breached the conditions of her bail and ended up in Holloway pending trial. Is there anything this otherwise sensible woman won’t sabotage for this virtual stranger?

With almost crashing inevitability, Yvonne finally learned what the rest of the world had suspected three episodes before - namely that Mark Costley was not a 007 figure of her fantasies, but a Walter Mitty figure intent on building a glamorous persona. Turns out she’d risked her job, her marriage, her freedom all for some snake oil salesman. Whoops! 

Yvonne is faced with the extent of Mark's deception

Now that’s sorted, what else do we still need to know? Well… 

1. What actually went on inside George Selway’s house before Costley came running out, urging Yvonne to drive, thereby roping her into the crime?

2. Why did he take Yvonne’s phone?  

3. Gary’s being so supportive - how long before he finds out the true nature of his wife’s relationship with Costley, and how will he react? We’ve seen he can be a bit handy with the kitchen knife when called for.

Mark Costley's change of plea may cost Yvonne her freedom

4. Now Costley’s entered a plea of diminished responsibility, does that really sound like the cool actions of the 007 figure Yvonne thinks him to be? We’re still not sure what he does, if anything... 

5. If Costley’s plea is accepted, where will that leave Yvonne, still accused of cooking up the murder plan? 

6. Will her marriage and family life survive her eventual fate, and has learned her lesson about the colour of the respective grass, etc? 

‘Apple Tree Yard’ concludes on Monday evening at 9pm on BBC One. Catch up on BBC iPlayer. 

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