Fresh from a night of partying for the show's fifth birthday, the reality star looked lovely in her slim-fitting black tracksuit and baseball hat when she was snapped on Wednesday morning (25 May).
Marnie, 24, had looked smokin' hot the night before in a figure-hugging black playsuit as she joined her co-stars at MTV studios in Camden, London to celebrate five years since the show went on air.
Five whole years!
She joined the show full time in series seven, arriving in the first episode and introducing herself as Sophie Kasaei's cousin. While Sophie left later that series, Marnie has remained a main cast member ever since - although she did briefly quit the show last year.
After getting engaged to ex-TOWIE star Ricky Rayment in Greece, she opted to leave the MTV show, telling fans she wanted to focus on her relationship. But following her split with Ricky, she returned to the house for the 12th series... and picked things up with co-star Aaron Chalmers.
She recently told Star magazine they are dating... but had a warning for Aaron if he doesn't make it official before filming for series 13 starts. "If I'm not Aaron's girlfriend by the time we go in, I'm going to leave it and be single with the girls," she said. "I can't do a full series of plodding on."