Show #54 (season 4, edition 18/season finale)

Debut: FRIDAY, JULY 1 (11:00-11:30 p.m. ET/PT)

Other HBO playdates: July 1 (12:30 a.m.), 2 (3:50 a.m.), 4 (12:40 a.m.), 5 (5:30 p.m.) and 6 (7:15 p.m.)

HBO2 playdate: July 6 (1:30 a.m.)

The show is also available on HBO NOW, HBO GO and HBO On Demand.

"The New $pace Race": Decades after the Apollo missions, a new era of manned spaceflight is dawning, and this time, the destination is Mars. NASA and a growing community of private companies have set their sights on the Red Planet and are developing the technologies to get there. Thomas Morton reports on the preparations for humanity's next great adventure.

"Closing Gitmo": The American prison at Guantanamo Bay, Cuba, is one of the most controversial issues of the post-9/11 era. President Obama promised to close the facility, but months from the end of his presidency, it remains open - and the reality of life there remains a mystery. Gianna Toboni meets with ex-detainees who survived Gitmo, and with the general who built it, to find out what really happens behind the camp's walls.