The actress, who plays bride-to-be Ruby Button, explained that she can understand why Esther (Jazmine Franks) and Bart (Jonny Clarke) resort to desperate measures when her character's big day arrives next week.
When the sixth formers plough through Ste, Doug, Tony and Cindy's joint wedding venue in a mini-bus next Wednesday (November 14), Esther and Bart have been chasing the vehicle in a last-ditch attempt to prevent Ruby from tying the knot.
Ruby, her fiancé Martin 'Jono' Johnson (Dylan Llewellyn) and the other teens are on the way to Gretna Green for the romantic ceremony, but Esther fears that her friend is making a terrible mistake.
Although faulty brakes on the mini-bus are the main cause of the crash, the dangerous behaviour of Esther and Bart is also a contributing factor.
Shaffer told Digital Spy of the pair's antics: "You'll have to wait and see whether Esther and Bart are blamed, but I do feel sorry for them because they were doing it out of the goodness of their hearts.
"Esther thinks it isn't right for Ruby to run off and marry Jono in secret, as she's doing it without permission from the Osbornes. Bart is looking out for his friend too, so it'd be a shame if they did face a backlash. They're doing it out of concern, but I think a certain amount of blame does have to lie with them!"
Shaffer revealed that she was delighted to be involved in the dramatic episodes, which will claim the lives of at least two characters.
She commented: "It was definitely long hours filming the scenes, but it was also absolutely amazing to be involved in. It was definitely the best thing that I've done since joining the Hollyoaks cast.
"We all got knocked about doing some of the scenes in the van. The day afterwards, I had huge bruises all over me and I was like, 'Oh my God, we did work really hard!' But there were obviously stunt doubles and dummies for the more serious stuff. It was hard, but it was definitely worth it."
Hollyoaks airs weeknights at 6.30pm on Channel 4, with first look screenings at 7pm on E4.
Photo gallery - Hollyoaks crash and explosion.
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