In 2009, Mensah played Leslie in
The Film You Did Not See. She spent the next few years landing roles in short films like 2010 comedy
Behold the Swelling Scene, 2012 comedy
Alternate Sides, and the 2013 biographical drama
Daadi. In 2014, Mensah played Sade, Nigerian-Ghanaian expat in
An African City. The web series created by
Nicole Amarteifio was dubbed "Africa's answer to Sex and the City". She reprised the role for season two. Mensah has starred in various off-Broadway roles including
Nollywood Dreams, reprising the role of Dede in after the production shut down due to COVID-19. Other credits include
The Bacchae,
Mother Courage and Her Children,
Inked Baby, and
A Question of Impeachment. In 2016, she starred as Clare in the Obie Award-winning play, ''I'll Never Love Again.
In 2017 she played Tamyra in Man from Nebraska,
for which she earned an Outer Critics Circle Award nomination for Outstanding Featured Actress. In 2020, she co-starred in Farewell Amor'' as Linda, which premiered at the 2019 Sundance Film Festival's U.S. Dramatic Competition. In 2021, Mensah premiered
Queen of Glory, a film about a Ghanaian-American academic who inherits a Christian bookstore after the passing of her mother. Mensah wrote, directed, and starred in the film which was completed in 30 days, but took over seven years total to complete. She cited Zhang Yimou's
Raise the Red Lantern, Wong Kar-wai's
In the Mood For Love, films by the Duplass Brothers, Kevin Smith's
Clerks, and Lena Dunham's
Tiny Furniture as influences. The film was funded through investors, Kickstarter campaigns, and Mensah's own savings.
Queen of Glory premiered at the 2021 Tribeca Film Festival U.S. Narrative Competition. Mensah won Best New Narrative Director and Special Jury Prize for Artistic Expression. In February 2022, the film was acquired by Film Movement with plans for a theatrical and video-on-demand release. It won numerous film festival prizes, including two awards from the
Champs-Élysées Film Festival and the inaugural California Film Institute's Mind the Gap Creation Prize. In 2021,
The Chair premiered on Netflix, in which Mensah portrays Yasmin "Yaz" McKay, a popular English professor. Mensah has a recurring role on
The Diplomat, which premiered on Netflix in 2023, portraying Billie Appiah, the
Chief of Staff to the President of the United States. She also appeared on Broadway in 2023 in ''
Jaja's African Hair Braiding.'' == Filmography ==