Morris was taking acting classes and actively pursuing an acting career when she was asked by Woodlee to teach the choreography for Beyoncé's "Single Ladies" dance to the Glee actors.
At the same time, the show was looking for a third cheerleader, and Morris ended up landing the role of Brittany.
Initially a background character who hardly ever spoke, the role grew as writers discovered Morris had a gift for delivering one-liners.
Jarrett Wieselman of the New York Post opined that Morris had "emerged as one of the funniest second bananas on TV right now" and a LA Times writer mentioned having a "comedy crush on Morris, who plays the galactically dim Glee Club cheerleader Brittany".

When a promotional clip for the episode "Sectionals" indicated that Brittany Pierce and Santana Lopez had slept together, Dorothy Snarker, writing for lesbian entertainment website After Ellen, praised the pairing, referring to them by the portmanteau "Brittana".
Snarker called the two her "new favorite Glee pairing", commenting that: "While Heather Morris (Brittany) and Naya Rivera (Santana) have had minimal screen time, they've made it count.
Heather in particular has brought the laughs as the Cheerio least likely to get a Mensa invitation.
Never mind Finn and Rachel — I'm on Team Brittana now."

Morris' role became more prominent during the final nine episodes of season one and, due to the overwhelmingly positive response to her character, was promoted to official series regular status during season two.
She was at the center of the second episode, "Britney/Brittany" (a tribute to Britney Spears), where she made her singing debut covering Spears' "I'm a Slave 4 U" solo and dueting with Naya Rivera on "Me Against the Music".
She later got many other singing and dancing solos.
The second half of season two saw Morris' character engage in a lesbian storyline with Rivera's character.
The arc and Rivera's and Morris' performances were met with critical acclaim.
As on Glee, Morris was best friends in real life with co-star Rivera, until Rivera’s death in 2020.

In Season 3, her and Rivera's characters continue with the lesbian storyline.
Morris had a large role in the episode "Prom-asaurus".
During the season finale, she reveals that she has an 0.0 GPA and that she will not be graduating.

During the 2011 Glee Tour, Morris performed Britney Spears' song "I'm a Slave 4 U".
She also had a dance spotlight with castmate Harry Shum Jr. during Naya Rivera's performance of "Valerie," and was one of the dancers in the "Single Ladies" and "Safety Dance" numbers.

Morris co-wrote and appeared in a January 2011 video for the comedy website Funny or Die, "Nuthin' But A Glee Thang" a parody of "Nuthin' but a 'G' Thang" by Dr. Dre featuring Snoop Dogg.
Co-written with actresses Ashley Lendzion and Riki Lindhome, the video features appearances from Modern Family's Sofia Vergara and Morris' Glee castmates Matthew Morrison, Cory Monteith, Harry Shum Jr., and Naya Rivera.

On June 28, 2013, it was reported that Morris would not be returning as regular on Glee's fifth season.
However, Morris reprised her role for the show's hundredth episode and the final episode of the show's fifth season.
Morris also appeared in five episodes in the show's sixth and final season, including the series finale.
Morris was taking acting classes and actively pursuing an acting career when she was asked by Woodlee to teach the choreography for Beyoncé's "Single Ladies" dance to the Glee actors. At the same time, the show was looking for a third cheerleader, and Morris ended up landing the role of Brittany. Initially a background character who hardly ever spoke, the role grew as writers discovered Morris had a gift for delivering one-liners. Jarrett Wieselman of the New York Post opined that Morris had "emerged as one of the funniest second bananas on TV right now" and a LA Times writer mentioned having a "comedy crush on Morris, who plays the galactically dim Glee Club cheerleader Brittany".
When a promotional clip for the episode "Sectionals" indicated that Brittany Pierce and Santana Lopez had slept together, Dorothy Snarker, writing for lesbian entertainment website After Ellen, praised the pairing, referring to them by the portmanteau "Brittana". Snarker called the two her "new favorite Glee pairing", commenting that: "While Heather Morris (Brittany) and Naya Rivera (Santana) have had minimal screen time, they've made it count. Heather in particular has brought the laughs as the Cheerio least likely to get a Mensa invitation. Never mind Finn and Rachel — I'm on Team Brittana now."
Morris' role became more prominent during the final nine episodes of season one and, due to the overwhelmingly positive response to her character, was promoted to official series regular status during season two. She was at the center of the second episode, "Britney/Brittany" (a tribute to Britney Spears), where she made her singing debut covering Spears' "I'm a Slave 4 U" solo and dueting with Naya Rivera on "Me Against the Music". She later got many other singing and dancing solos. The second half of season two saw Morris' character engage in a lesbian storyline with Rivera's character. The arc and Rivera's and Morris' performances were met with critical acclaim. As on Glee, Morris was best friends in real life with co-star Rivera, until Rivera’s death in 2020.
In Season 3, her and Rivera's characters continue with the lesbian storyline. Morris had a large role in the episode "Prom-asaurus". During the season finale, she reveals that she has an 0.0 GPA and that she will not be graduating.
During the 2011 Glee Tour, Morris performed Britney Spears' song "I'm a Slave 4 U". She also had a dance spotlight with castmate Harry Shum Jr. during Naya Rivera's performance of "Valerie," and was one of the dancers in the "Single Ladies" and "Safety Dance" numbers.
Morris co-wrote and appeared in a January 2011 video for the comedy website Funny or Die, "Nuthin' But A Glee Thang" a parody of "Nuthin' but a 'G' Thang" by Dr. Dre featuring Snoop Dogg. Co-written with actresses Ashley Lendzion and Riki Lindhome, the video features appearances from Modern Family's Sofia Vergara and Morris' Glee castmates Matthew Morrison, Cory Monteith, Harry Shum Jr., and Naya Rivera.
On June 28, 2013, it was reported that Morris would not be returning as regular on Glee's fifth season. However, Morris reprised her role for the show's hundredth episode and the final episode of the show's fifth season. Morris also appeared in five episodes in the show's sixth and final season, including the series finale.
Heather Morris