New Kids On The Block are stepping into the ring for 2015. The pop phenoms stopped by Good Morning America this morning to announce THE MAIN EVENT, a summer headlining tour featuring very special guests, Grammy Award-winning and multi-platinum selling artists TLC and Nelly. NKOTB surprised viewers with a special reveal of TLC and a personal message from Nelly (who is currently overseas with the armed forces). The groups hinted at possible collaborations and other exciting possibilities while on the road this summer, sending fans into a frenzy across social media. The tour, promoted by Live Nation, kicks-off on May 1 in Las Vegas, Nev. and will stop in over 30 cities across North America including Washington, D.C. on June 10 at Verizon Center.