Scene from Uncharted 2. Could Nathan Drake be absent from the series' next installment? Courtesy/Wikipedia

Santa Monica, Calif.-based developer Naughty Dog recently announced a fourth installment of its popular Playstation series "Uncharted." A teaser trailer for "Uncharted 4," which was released Thursday on PlayStation’s YouTube channel, features a male voiceover from an unknown character and a map moving from southern Africa to Madagascar .

What conclusions can we draw from the "Uncharted 4" trailer?

1. The male voice does not sound like Nathan Drake, the main protagonist of the "Uncharted" series. Drake has starred in “Uncharted: Drake’s Fortune,” “Uncharted 2: Honor Among Thieves,” “Uncharted 3: Drake’s Deception” and “Uncharted: Golden Abyss” for the PS Vita. Has Drake been replaced by an entirely new hero? Is he too busy starring in Subway commercials to go looking for fortunes anymore?

2. The vintage-looking map in "Uncharted 4" spans from the tip of southern Africa to Madagascar. As expected, Naughty Dog developers chose an interesting and culturally rich location for the fourth series installment from Naughty Dog.

3. The narrator from the "Uncharted 4" teaser seems pretty angry and hell-bent on revenge. In a tone that is reminiscent of Dexter Morgan right before a kill, the "Uncharted 4" ad’s character begins by saying that “some chains can never be broken,” adding that he “lost 15 years, buried alive, erased…rotting.” The anonymous voice also goes on to tell an unknown listener that “you can’t outrun the past…you owe me.” Could this be an entirely new character – or even Nathan Drake as an old man with a more mature voice, recounting old stories at the retired treasure hunter rest home?

While there is no set release date for "Uncharted 4," PS4 and Sony fans are excited for the game’s launch, since the Uncharted series is one of the most popular franchises for the PlayStation.

Watch the "Uncharted 4" trailer below and let us know what you think.