A user (external party) is interested in accessing the real-time data from some designated drones of a particular fly zone in the Internet of Drones (IoD) deployment. However, to provide this facility the user needs to be authenticated by an accessed remote drone and vice-versa. After successful authentication both parties can establish a secret session key for the secure communication. To handle this important problem in IoD environment, we design a novel temporal credential based anonymous lightweight user authentication mechanism for IoD environment, called TCALAS. A detailed security analysis using formal security under the broadly applied Real-Or-Random (ROR) model, formal security verification under the broadly used software verification tool, known as Automated Validation of Internet Security Protocols and Applications (AVISPA), and also informal security analysis reveal that TCALAS has the capability to resist various known attacks against passive/active adversary. In addition, a detailed comparative study has been conducted for TCALAS and other related schemes, and the study also reveals that TCALAS provides better security and functionality features, and lower costs in both computation & communication as compared to existing schemes.