Morningstar harshly mocked her by saying she made Archimedes look like an Ogron when her experiments failed to work properly as she tried to create portals that led into the Time Vortex. He wanted to use time travel for nefarious ends, threatened to cut her funding, which Stralla found unfair, and called him a "big bully" behind his back while she was close to a breakthrough.
Eventually, Cushing managed to open a portal into the Time Vortex and rushed to tell Morningstar of the good news. Morningstar wanted to know if he could travel through time, though she said it was still early days and she still needed to do some research. Stralla didn't understand why Morningstar needed to bother opening time travel up as a tourism business since he was rich already.
At the time, the Eighth Doctor and Liv Chenka were travelling through the vortex looking for Helen Sinclair, who was with the Eleven, encountered temporal distortions in the vortex, forcing them to investigate and they shut down the gateway. When Cushing and Morningstar returned to the laboratory to find the gateway shut down, Morningstar flew into a rage, cutting off her contract and firing her, threatening to destroy her reputation and Stralla snapped when she tried to convince him she could build a time machine and get it working. She killed him and shoved him through the gateway when she turned it back on to hide the body to stop the station security system tracking him down. (AUDIO: How to Make a Killing in Time Travel)