Elizabeth Olsen loved wearing a "pregnant belly" in 'WandaVision'

Asked which costume was her favourite, she said: "The one I wore for the '70s because I loved wearing a pregnant belly."

'WandaVision' sees Elizabeth as Wanda and Paul Bettany as Vision living as couple in a sleepy suburban town trying to hide their identities and the Disney+ show takes place over several periods.

Elizabeth loved exploring the different costumes for each timespan as the designers have had to think about every little detail to ensure the looks are authentic.

Speaking to America's OK! magazine, she said: "There was so much effort that went into picking out these vintage fabrics, the wigs and the different haircuts. You had to make it specific to every decade. There had to be a certain type of curl, different types of eyelashes and a certain shape of the nails. The detail and craftmanship still blows my mind."

What's more, the Marvel series makes a number of references to sitcoms and the cast was instructed to undertake a "boot camp" where they were instructed to watch the sitcoms to fully understand the jokes and references.

She added: "We had a boot camp where the whole cast watched every single show that we made a direct reference to. That way, we could authentically recreate the style and the tone, how to walk, talk and dress, whether it was 'Bewitched' or 'Malcolm in the Middle'. So there was a lot of dorky actor preparation we got to do."

However, Elizabeth loved swapping a busy film set for a small studio set with a live audience though it initially "confused" her.

She explained: "There was so much adrenaline playing to an audience instead of the camera. It confused my brain a bit, but it really ripped the Band-Aid off and launched us bravely into full-throttle sitcom mode."