The 10 year old bade farewell to her long blonde locks on Sunday (9th), and donated them to a total stranger during a fundraising party she held for her birthday.
Maisie's hair was sent to the Little Princess Trust, where it'll be made into a wig and given free to a child who lost their hair to cancer treatment.
Maisie was inspired by singer Jessie J, who she saw in concert at the Odyssey not long after the star shaved her head for Comic Relief.
"Jessie that she wanted to do it to encourage people that it wasn't what you look like that counts, but being happy with who you are," explained the 10 year old.
"I think the same, and if I can show that and help a kid like me who doesn't have a choice about changing their looks, that's brilliant."
In addition to donating her hair, Maisie has embarked on an ambitious fundraising project aiming to raise over £1,000 for the Little Princess Trust.
She sacrificed a birthday party to instead host Sunday's fundraising party, during which she braved the shears.
Maisie had encouraged her friends to bring a donation instead of a present, contributing to a fund that has already seen her raise enough cash for two £350 wigs.