XIII for the PC is currently free on Good Gold Games (GoG) until April 1st.
The plot for XIII is the President of the United States of America has been assassinated and you're the world's prime suspect. The FBI, the CIA, and a gang of murderous killers are trying to hunt you down. Stricken with amnesia you remember nothing, not even who you are. You're on your own and there is no one you can trust. All you have is a safe deposit key, a mysterious tattoo, and a gun. Clear your name, solve the mystery, and catch the true assassin before he strikes again.
Certainly a classic game worth playing if you have a bit of free time this Easter weekend.
Claim: XIII on GoG (Click the Go to giveaway to claim your free copy of XIII)