See here for a recent post of mine on this subject. The article linked ITT by /u/Silver_Agocchie is also useful, and cites extensively from Phil Sabin's "The Face of Roman Battle" (Journal of Roman Studies 90 (2000) 1-17) which is one of the most important publications shaping the modern understanding of how ancient battles worked.

The short version is no, they were probably nothing like what you see in the movies. The casualty rate in the sort of chaotic melee we see in movies would be far too high; no man in his right mind would be willing to face such slaughter. In reality, battles would have been far more tentative, with prolonged sporadic violence between mostly defensive formations, until one side or the other lost its nerve.