Rupert Gardner was the mess sergeant of the new Normandy. He was hired on by Cerberus and had been a proud member. His job includes custodian work and making meals for the crew members. He started out with making meals from military provisions, which was not well-liked by the crew, but when Shepard was able to receive some high quality ingredients from the Zakera Ward, his meal improved immensely.
In Mass Effect 3, it's unclear as to why he didn't return if he survived, but he wasn't seen again.
The Fayelons Story[]
Gardner continued to be the Normandy's Mess Sergeant dispite it not being the original idea in Mass Effect 3. He fixed up the Fayelons' first meal since their arrival in their galaxy. However, he prepared a seafood gumbo, which greatly set off Splash due to her extreme hatred for fish food. From there, she through the first of her "fishy tantrums" that was witnessed by the crew members, to which she through everything around while making death threats to him in a funny way. Thankfully, her friends held her back, so she didn't hurt him as well as had Jewel placed on of her Fantasy Crystals on her to calm her down. Gardner regretted preparing the gumbo and decided to make a gazpacho to make up for setting her off by accident. The gazpacho to this day had been a favorite of Splash's that he had ever made. She did regret throwing a tantrum and nearly trying to harm him and they remained on good terms ever since.
He continues to cook for the girls, making sure to avoid any dishes with seafood in it like his life depends on it, because it pretty much does.
Overtime, he has become very helpful to the girls by providing them with regular meals at the recommendation of Mordin. He has been a tremendous help with keeping the girls' strength up.
During Episode 50, he has stood by the sidelines, watching Mayweather cook, to which is impressed with, being that she is a young adolencent who seems to know how to cook.