Topolsky was the FBI agent disguised as the new school guidance counselor in season one of Roswell and was at one time the only female agent of the F.B.I.'s Special Unit. She has a photographic memory.
After Sheriff Jim Valenti informed the FBI of his suspicions about Max Evans being an alien, the FBI sent her to Roswell, New Mexico where she diguised herself as a guidance counselor at Max's school. However, when Liz saw her with Michael Guerin's file she starts to suspect her.
She originally appeared as a subsitute teacher in Liz's class. Michael was absent that day, when she realized he was absent, she started asking Max a lot of questions about him. This made Liz suspiscious but Max thought it was no big deal. Liz ran into her in the hallway and all her files spilled. Liz helped pick them up and saw that she had Michaels file with her. Liz told Max that she thought Mrs. Topolsky was an alien hunter he thought it seemed ridiculous. However, Max saw her talking to part of the Sheriffs depatment and shaking hands with him, Max started to realize Liz might be right. Max and Liz started spying on her and they saw her go to Michael's house when he wasn't home. At school the next day, Mrs. Topolski told Liz that she had seen her at Michaels house that night. She said that she wasn't really a substitute teacher, she was a guidance councellor and Michael was in serious trouble.
In the episode Monsters, Ms. Topolsky announced to the all of the students at Roswell high that she would be giving them interviews to discuss their plans for the future. When she is interviewing Liz, Liz tells her that she'd like to be a molecular biologist. Ms. Topolsky notes that Liz is very "together" and will probably succeed in life because she always seems to be prepared. While she interviewed Max, she showed him a picture of a playground and asks him where he sees himself. He replied with, "Behind one of the trees, watching everyone else". Ms. Topolsky told him that he should come out from behind the tree.
Later on in the season, with help from Sheriff Jim Valenti, Liz revealed her true colours and she was killed. Sheriff Valenti learns that Topolsky was killed in a suspicious fire.