The brute was easily stronger than Marcus, and much quicker than the executive would have thought, quick enough to land a few solid blows, mostly because of Marcus making sure nothing befell Kat as she made her escape. Once she was out of sight, Marcus' own speed and dexterity came fully into play. Marcus' talents were simply inherited and privately trained, not precisely honed and perfected like Kat's, but he had more than enough to deal with the bruiser before him.
Kat would make it to the car with no trouble. The doctor had been so anxious to restore his studies of her that he'd forgotten to take into consideration her brother's combat capabilities. As such, he thought the brute in the waiting room would have been enough.
It wouldn't take long for Marcus to drop the man. He then looked down the hallway. He'd heard the car peel away earlier, so she was safe. He looked back to the room they'd just left, then down the hallway again, and back. His eyes narrowed as the decision was made and he walked back into the office and kicked the door open that had been shut again. He took the throwing knives out from their hiding spot and readied them as he glared at Dr. Roe. There was no awaiting comment. He spoke low and loud. "Why is she afraid of you!?"