In this mid-term project, we are given a full implementation of a Nature-DQN agent, and a series of assignments. Firstly, we need to read through the implementation and explain in detail what each component is responsible for and how the components are connected together. Chen Long (19335019) is mainly responsible for this part. Then we should pick one of the given questions to research into. After discussion, we decide to research into Question 2(Can you improve the performance using Dueling DQN?) and use Dueling DQN to improve the performance in the Breakout game. Chen Haoran (19335016) is mainly responsible for this part.